Oracle SQL*Loader Reference manual

PartII

SQL*Loader

The chapters in this section describe the SQL*Loader utility:

Chapter 3, "SQL*Loader Concepts"

This chapter introduces SQL*Loader and describes its features. It also introduces data loading concepts (including object support). It discusses input to SQL*Loader, database preparation, and output from SQL*Loader.

Chapter 4, "SQL*Loader Command-Line Reference"

This chapter describes the command-line syntax used by SQL*Loader. It discusses command-line arguments, suppressing SQL*Loader messages, sizing the bind array, and more.

Chapter 5, "SQL*Loader Control File Reference"

This chapter describes the control file syntax you use to configure SQL*Loader and to describe to SQL*Loader how to map your data to Oracle format. It provides detailed syntax diagrams and information about specifying datafiles, tables and columns, the location of data, the type and format of data to be loaded, and more.

Chapter 6, "Field List Reference"

This chapter describes the field list section of a SQL*Loader control file. The field list provides information about fields being loaded, such as position, datatype, conditions, and delimiters.

Chapter 7, "Loading Objects, LOBs, and Collections"

This chapter describes how to load objects in various formats, as well as loading object tables and REF columns. This chapter also discusses loading LOBs and columns.

Chapter 8, "SQL*Loader Log File Reference"

This chapter describes the information contained in SQL*Loader log file output.

Chapter 9, "Conventional and Direct Path Loads"

This chapter describes the differences between a conventional path load and a direct path load. A direct path load is a high-performance option that significantly reduces the time required to load large quantities of data.

Chapter 10, "SQL*Loader Case Studies"

This chapter presents case studies that illustrate some of the features of

SQL*Loader. It demonstrates the loading of variable-length data, fixed-format records, a free-format file, multiple physical records as one logical record, multiple tables, direct path loads, and loading objects, collections, and REF columns.

3

SQL*Loader Concepts

This chapter explains the basic concepts of loading data into an Oracle database with SQL*Loader. This chapter covers the following topics:

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SQL*Loader Features

SQL*Loader Control File

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Input Data and Datafiles

LOBFILEs and Secondary Datafiles (SDFs)

Data Conversion and Datatype Specification

Discarded and Rejected Records

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Log File and Logging Information

Conventional Path Loads, Direct Path Loads, and External Table Loads

Loading Objects, Collections, and LOBs

Partitioned Object Support

Application Development: Direct Path Load API

SQL*Loader Features

SQL*Loader loads data from external files into tables of an Oracle database. It has a powerful data parsing engine that puts little limitation on the format of the data in the datafile. You can use SQL*Loader to do the following:

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Load data from multiple datafiles during the same load session.

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Load data into multiple tables during the same load session.

Specify the character set of the data.

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SQL*Loader Features

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Selectively load data (you can load records based on the records’ values).

Manipulate the data before loading it, using SQL functions.

Generate unique sequential key values in specified columns.

Use the operating system’s file system to access the datafiles.

Load data from disk, tape, or named pipe.

Generate sophisticated error reports, which greatly aids troubleshooting.

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Load arbitrarily complex object-relational data.

Use secondary datafiles for loading LOBs and collections.

Use either conventional or direct path loading. While conventional path loading is very flexible, direct path loading provides superior loading performance. See

Chapter 9 .

Use a DB2 Load Utility control file as a SQL*Loader control file with few or no changes involved. See Appendix B .

A typical SQL*Loader session takes as input a control file, which controls the behavior of SQL*Loader, and one or more datafiles. The output of SQL*Loader is an

Oracle database (where the data is loaded), a log file, a bad file, and potentially, a discard file. An example of the flow of a SQL*Loader session is shown in Figure 3–1 .

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SQL*Loader Control File

Figure 3–1 SQL*Loader Overview

Bad

Files

Datafiles

Log

File

SQL*Loader

Loader

Control

File

Bad

Files

Files

Discard

Files

Files

Database

Table

Indexes

Table

Tables

SQL*Loader Control File

The control file is a text file written in a language that SQL*Loader understands.

The control file tells SQL*Loader where to find the data, how to parse and interpret the data, where to insert the data, and more.

Although not precisely defined, a control file can be said to have three sections.

The first section contains session-wide information, for example:

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Global options such as bindsize, rows, records to skip, and so on

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INFILE

clauses to specify where the input data is located

Data to be loaded

The second section consists of one or more INTO TABLE blocks. Each of these blocks contains information about the table into which the data is to be loaded, such as the table name and the columns of the table.

The third section is optional and, if present, contains input data.

Some control file syntax considerations to keep in mind are:

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Input Data and Datafiles

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The syntax is free-format (statements can extend over multiple lines).

It is case insensitive; however, strings enclosed in single or double quotation marks are taken literally, including case.

In control file syntax, comments extend from the two hyphens (--) that mark the beginning of the comment to the end of the line. The optional third section of the control file is interpreted as data rather than as control file syntax; consequently, comments in this section are not supported.

The CONSTANT keyword has special meaning to SQL*Loader and is therefore reserved. To avoid potential conflicts, Oracle Corporation recommends that you do not use the word CONSTANT as a name for any tables or columns.

See Also:

semantics

Chapter 5 for details about control file syntax and

Input Data and Datafiles

SQL*Loader reads data from one or more files (or operating system equivalents of files) specified in the control file. From SQL*Loader’s perspective, the data in the datafile is organized as records. A particular datafile can be in fixed record format, variable record format, or stream record format. The record format can be specified in the control file with the INFILE parameter. If no record format is specified, the default is stream record format.

Note:

If data is specified inside the control file (that is, INFILE * was specified in the control file), then the data is interpreted in the stream record format with the default record terminator.

Fixed Record Format

A file is in fixed record format when all records in a datafile are the same byte length. Although this format is the least flexible, it results in better performance than variable or stream format. Fixed format is also simple to specify. For example:

INFILE datafile_name "fix n "

This example specifies that SQL*Loader should interpret the particular datafile as being in fixed record format where every record is n bytes long.

Example 3–1 shows a control file that specifies a datafile that should be interpreted in the fixed record format. The datafile in the example contains five physical

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Input Data and Datafiles records. Assuming that a period (.) indicates a space, the first physical record is

[001,...cd,.] which is exactly eleven bytes (assuming a single-byte character set). The second record is [0002,fghi,\n] followed by the newline character (which is the eleventh byte), and so on. Note that newline characters are not required with the fixed record format.

Note that the length is always interpreted in bytes, even if character-length semantics are in effect for the file. This is necessary because the file could contain a mix of fields, some of which are processed with character-length semantics and others which are processed with byte-length semantics. See Character-Length

Semantics on page 5-22.

Example 3–1 Loading Data in Fixed Record Format

load data infile ’example.dat’ "fix 11" into table example fields terminated by ’,’ optionally enclosed by ’"’

(col1, col2) example.dat:

001, cd, 0002,fghi,

00003,lmn,

1, "pqrs",

0005,uvwx,

Variable Record Format

A file is in variable record format when the length of each record in a character field is included at the beginning of each record in the datafile. This format provides some added flexibility over the fixed record format and a performance advantage over the stream record format. For example, you can specify a datafile that is to be interpreted as being in variable record format as follows:

INFILE " datafile_name " "var n "

In this example, n specifies the number of bytes in the record length field. If n is not specified, SQL*Loader assumes a length of 5 bytes. Specifying n larger than 40 will result in an error.

Example 3–2 shows a control file specification that tells SQL*Loader to look for data in the datafile example.dat and to expect variable record format where the record length fields are 3 bytes long. The example.dat datafile consists of three physical records. The first is specified to be 009 (that is, 9) bytes long, the second is 010 bytes

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Input Data and Datafiles long (that is, 10, including a 1-byte newline), and the third is 012 bytes long (also including a 1-byte newline). Note that newline characters are not required with the variable record format. This example also assumes a single-byte character set for the datafile.

The lengths are always interpreted in bytes, even if character-length semantics are in effect for the file. This is necessary because the file could contain a mix of fields, some processed with character-length semantics and others processed with byte-length semantics. See Character-Length Semantics on page 5-22.

Example 3–2 Loading Data in Variable Record Format

load data infile ’example.dat’ "var 3" into table example fields terminated by ’,’ optionally enclosed by ’"’

(col1 char(5),

col2 char(7)) example.dat:

009hello,cd,010world,im,

012my,name is,

Stream Record Format

A file is in stream record format when the records are not specified by size; instead

SQL*Loader forms records by scanning for the record terminator. Stream record format is the most flexible format, but there can be a negative effect on performance.

The specification of a datafile to be interpreted as being in stream record format looks similar to the following:

INFILE datafile_name

[

"str terminator_string"

]

The terminator_string is specified as either ’char_string’ or X’hex_ string’

where:

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’ char_string’ is a string of characters enclosed in single or double quotation marks

X’hex_string’

is a byte string in hexadecimal format

When the terminator_string contains special (nonprintable) characters, it should be specified as a X’hex_string’. However, some nonprintable characters can be specified as (’char_string’) by using a backslash. For example:

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\n

indicates a line feed

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Input Data and Datafiles

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\t

indicates a horizontal tab

\f

indicates a form feed

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\v

indicates a vertical tab

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\r

indicates a carriage return

If the character set specified with the NLS_LANG parameter for your session is different from the character set of the datafile, character strings are converted to the character set of the datafile. This is done before SQL*Loader checks for the default record terminator.

Hexadecimal strings are assumed to be in the character set of the datafile, so no conversion is performed.

On UNIX-based platforms, if no terminator_string is specified, SQL*Loader defaults to the line feed character, \n.

On Windows NT, if no terminator_string is specified, then SQL*Loader uses either \n or \r\n as the record terminator, depending on which one it finds first in the datafile. This means that if you know that one or more records in your datafile has \n embedded in a field, but you want \r\n to be used as the record terminator, you must specify it.

Example 3–3 illustrates loading data in stream record format where the terminator string is specified using a character string, ’|\n’. The use of the backslash character allows the character string to specify the nonprintable line feed character.

Example 3–3 Loading Data in Stream Record Format

load data infile ’example.dat’ "str ’|\n’" into table example fields terminated by ’,’ optionally enclosed by ’"’

(col1 char(5),

col2 char(7)) example.dat: hello,world,| james,bond,|

Logical Records

SQL*Loader organizes the input data into physical records, according to the specified record format. By default a physical record is a logical record, but for

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Input Data and Datafiles added flexibility, SQL*Loader can be instructed to combine a number of physical records into a logical record.

SQL*Loader can be instructed to follow one of the following logical record-forming strategies:

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Combine a fixed number of physical records to form each logical record

Combine physical records into logical records while a certain condition is true

See Also:

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Assembling Logical Records from Physical Records on page 5-27

Case Study 4: Loading Combined Physical Records on page 10-14 for an example of how to use continuation fields to form one logical record from multiple physical records

Data Fields

Once a logical record is formed, field setting on the logical record is done. Field setting is a process in which SQL*Loader uses control-file field specifications to determine which parts of logical record data correspond to which control-file fields.

It is possible for two or more field specifications to claim the same data. Also, it is possible for a logical record to contain data that is not claimed by any control-file field specification.

Most control-file field specifications claim a particular part of the logical record.

This mapping takes the following forms:

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The byte position of the data field’s beginning, end, or both, can be specified.

This specification form is not the most flexible, but it provides high field-setting performance.

The strings delimiting (enclosing and/or terminating) a particular data field can be specified. A delimited data field is assumed to start where the last data field ended, unless the byte position of the start of the data field is specified.

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The byte offset and/or the length of the data field can be specified. This way each field starts a specified number of bytes from where the last one ended and continues for a specified length.

Length-value datatypes can be used. In this case, the first n number of bytes of the data field contain information about how long the rest of the data field is.

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Data Conversion and Datatype Specification

See Also:

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SQL*Loader Datatypes on page 6-7

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Specifying Delimiters on page 6-24

LOBFILEs and Secondary Datafiles (SDFs)

LOB data can be lengthy enough that it makes sense to load it from a LOBFILE. In

LOBFILEs, LOB data instances are still considered to be in fields (predetermined size, delimited, length-value), but these fields are not organized into records (the concept of a record does not exist within LOBFILEs). Therefore, the processing overhead of dealing with records is avoided. This type of organization of data is ideal for LOB loading.

For example, you might use LOBFILEs to load employee names, employee IDs, and employee resumes. You could read the employee names and IDs from the main datafiles and you could read the resumes, which can be quite lengthy, from

LOBFILEs.

You might also use LOBFILEs to facilitate the loading of XML data. You can use XML columns to hold data that models structured and semistructured data. Such data can be quite lengthy.

Secondary datafiles (SDFs) are similar in concept to primary datafiles. Like primary datafiles, SDFs are a collection of records, and each record is made up of fields. The

SDFs are specified on a per control-file-field basis. Only a collection_fld_spec can name an SDF as its data source.

SDFs are specified using the SDF parameter. The SDF parameter can be followed by either the file specification string, or a FILLER field that is mapped to a data field containing one or more file specification strings.

See Also:

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Loading LOB Data from LOBFILEs on page 7-23

Secondary Datafiles (SDFs) on page 7-31

Data Conversion and Datatype Specification

During a conventional path load, data fields in the datafile are converted into

columns in the database (direct path loads are conceptually similar, but the implementation is different). There are two conversion steps:

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Discarded and Rejected Records

1.

2.

SQL*Loader uses the field specifications in the control file to interpret the format of the datafile, parse the input data, and populate the bind arrays that correspond to a SQL INSERT statement using that data.

The Oracle database server accepts the data and executes the INSERT statement to store the data in the database.

The Oracle database server uses the datatype of the column to convert the data into its final, stored form. Keep in mind the distinction between a field in a datafile and a

column in the database. Remember also that the field datatypes defined in a

SQL*Loader control file are not the same as the column datatypes.

Discarded and Rejected Records

Records read from the input file might not be inserted into the database. Such records are placed in either a bad file or a discard file.

The Bad File

The bad file contains records that were rejected, either by SQL*Loader or by the

Oracle database server. Some of the possible reasons for rejection are discussed in the next sections.

SQL*Loader Rejects

Datafile records are rejected by SQL*Loader when the input format is invalid. For example, if the second enclosure delimiter is missing, or if a delimited field exceeds its maximum length, SQL*Loader rejects the record. Rejected records are placed in the bad file.

Oracle Rejects

After a datafile record is accepted for processing by SQL*Loader, it is sent to the

Oracle database server for insertion into a table as a row. If the Oracle database server determines that the row is valid, then the row is inserted into the table. If the row is determined to be invalid, then the record is rejected and SQL*Loader puts it in the bad file. The row may be invalid, for example, because a key is not unique, because a required field is null, or because the field contains invalid data for the

Oracle datatype.

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Conventional Path Loads, Direct Path Loads, and External Table Loads

See Also:

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Specifying the Bad File on page 5-11

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Case Study 4: Loading Combined Physical Records on page 10-14 for an example use of a bad file

The Discard File

As SQL*Loader executes, it may create a file called the discard file. This file is created only when it is needed, and only if you have specified that a discard file should be enabled. The discard file contains records that were filtered out of the load because they did not match any record-selection criteria specified in the control file.

The discard file therefore contains records that were not inserted into any table in the database. You can specify the maximum number of such records that the discard file can accept. Data written to any database table is not written to the discard file.

See Also:

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Case Study 4: Loading Combined Physical Records on page 10-14

Specifying the Discard File on page 5-14

Log File and Logging Information

When SQL*Loader begins execution, it creates a log file. If it cannot create a log file, execution terminates. The log file contains a detailed summary of the load, including a description of any errors that occurred during the load.

See Also:

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Chapter 8, "SQL*Loader Log File Reference"

Chapter 10, "SQL*Loader Case Studies" for sample log files

Conventional Path Loads, Direct Path Loads, and External Table Loads

SQL*Loader provides the following methods to load data:

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Conventional Path Loads

Direct Path Loads

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Conventional Path Loads, Direct Path Loads, and External Table Loads

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External Table Loads

Conventional Path Loads

During conventional path loads, the input records are parsed according to the field specifications, and each data field is copied to its corresponding bind array. When the bind array is full (or no more data is left to read), an array insert is executed.

See Also:

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Data Loading Methods on page 9-1

Bind Arrays and Conventional Path Loads on page 5-44

SQL*Loader stores LOB fields after a bind array insert is done. Thus, if there are any errors in processing the LOB field (for example, the LOBFILE could not be found), the LOB field is left empty. Note also that because LOB data is loaded after the array insert has been performed, BEFORE and AFTER row triggers may not work as expected for LOB columns. This is because the triggers fire before SQL*Loader has a chance to load the LOB contents into the column. For instance, suppose you are loading a LOB column, C1, with data and that you want a BEFORE row trigger to examine the contents of this LOB column and derive a value to be loaded for some other column, C2, based on its examination. This is not possible because the LOB contents will not have been loaded at the time the trigger fires.

Direct Path Loads

A direct path load parses the input records according to the field specifications, converts the input field data to the column datatype, and builds a column array.

The column array is passed to a block formatter, which creates data blocks in Oracle database block format. The newly formatted database blocks are written directly to the database, bypassing most RDBMS processing. Direct path load is much faster than conventional path load, but entails several restrictions.

See Also:

Direct Path Load on page 9-5

Parallel Direct Path

A parallel direct path load allows multiple direct path load sessions to concurrently load the same data segments (allows intrasegment parallelism). Parallel direct path is more restrictive than direct path.

See Also:

Parallel Data Loading Models on page 9-30

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Loading Objects, Collections, and LOBs

External Table Loads

An external table load creates an external table for data in a datafile and executes

INSERT

statements to insert the data from the datafile into the target table.

The advantages of using external table loads over conventional path and direct path loads are as follows:

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An external table load attempts to load datafiles in parallel. If a datafile is big enough, it will attempt to load that file in parallel.

An external table load allows modification of the data being loaded by using

SQL functions and PL/SQL functions as part of the INSERT statement that is used to create the external table.

See Also:

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Chapter 11, "External Tables Concepts"

Chapter 12, "External Tables Access Parameters"

Loading Objects, Collections, and LOBs

You can use SQL*Loader to bulk load objects, collections, and LOBs. It is assumed that you are familiar with the concept of objects and with Oracle’s implementation of object support as described in Oracle9i Database Concepts and in the Oracle9i

Database Administrator’s Guide.

Supported Object Types

SQL*Loader supports loading of the following two object types:

column-objects

When a column of a table is of some object type, the objects in that column are referred to as column-objects. Conceptually such objects are stored in their entirety in a single column position in a row. These objects do not have object identifiers and cannot be referenced.

If the object type of the column object is declared to be nonfinal, then SQL*Loader allows a derived type (or subtype) to be loaded into the column object.

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Loading Objects, Collections, and LOBs

row objects

These objects are stored in tables, known as object tables, that have columns corresponding to the attributes of the object. The object tables have an additional system-generated column, called SYS_NC_OID$, that stores system-generated unique identifiers (OIDs) for each of the objects in the table. Columns in other tables can refer to these objects by using the OIDs.

If the object type of the object table is declared to be nonfinal, then SQL*Loader allows a derived type (or subtype) to be loaded into the row object.

See Also:

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Loading Column Objects on page 7-1

Loading Object Tables on page 7-12

Supported Collection Types

SQL*Loader supports loading of the following two collection types:

Nested Tables

A nested table is a table that appears as a column in another table. All operations that can be performed on other tables can also be performed on nested tables.

VARRAYs

VARRAY s are variable sized arrays. An array is an ordered set of built-in types or objects, called elements. Each array element is of the same type and has an index, which is a number corresponding to the element’s position in the VARRAY.

When creating a VARRAY type, you must specify the maximum size. Once you have declared a VARRAY type, it can be used as the datatype of a column of a relational table, as an object type attribute, or as a PL/SQL variable.

See Also:

Loading Collections (Nested Tables and VARRAYs) on page 7-29 for details on using SQL*Loader control file data definition language to load these collection types

Supported LOB Types

A LOB is a large object type. This release of SQL*Loader supports loading of four

LOB types:

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BLOB:

a LOB containing unstructured binary data

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CLOB:

a LOB containing character data

NCLOB:

a LOB containing characters in a database national character set

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BFILE:

a BLOB stored outside of the database tablespaces in a server-side operating system file

LOBs can be column datatypes, and with the exception of the NCLOB, they can be an object’s attribute datatypes. LOBs can have an actual value, they can be null, or they can be "empty."

See Also:

Loading LOBs on page 7-18 for details on using

SQL*Loader control file data definition language to load these LOB types

Partitioned Object Support

SQL*Loader supports loading partitioned objects in the database. A partitioned object in an Oracle database is a table or index consisting of partitions (pieces) that have been grouped, typically by common logical attributes. For example, sales data for the year 2000 might be partitioned by month. The data for each month is stored in a separate partition of the sales table. Each partition is stored in a separate segment of the database and can have different physical attributes.

SQL*Loader partitioned object support enables SQL*Loader to load the following:

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A single partition of a partitioned table

All partitions of a partitioned table

A nonpartitioned table

Application Development: Direct Path Load API

Oracle Corporation provides a direct path load API for application developers. See the Oracle Call Interface Programmer’s Guide for more information.

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Application Development: Direct Path Load API

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4

SQL*Loader Command-Line Reference

This chapter describes the command-line parameters used to invoke SQL*Loader.

The following topics are discussed:

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Invoking SQL*Loader

Command-Line Parameters

Exit Codes for Inspection and Display

Invoking SQL*Loader

When you invoke SQL*Loader, you can specify certain parameters to establish session characteristics. Parameters can be entered in any order, optionally separated by commas. You specify values for parameters, or in some cases, you can accept the default without entering a value.

For example:

SQLLDR CONTROL=foo.ctl, LOG=bar.log, BAD=baz.bad, DATA=etc.dat

USERID=scott/tiger, ERRORS=999, LOAD=2000, DISCARD=toss.dis,

DISCARDMAX=5

If you invoke SQL*Loader without specifying any parameters, SQL*Loader displays a help screen similar to the following. It lists the available parameters and their default values.

sqlldr

...

SQL*Loader: Release 9.2.0.1.0 - Production on Wed Feb 27 12:06:17 2002

(c) Copyright 2002 Oracle Corporation. All rights reserved.

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Invoking SQL*Loader

Usage: SQLLDR keyword=value [,keyword=value,...]

Valid Keywords:

userid -- ORACLE username/password

control -- Control file name

log -- Log file name

bad -- Bad file name

data -- Data file name

discard -- Discard file name discardmax -- Number of discards to allow (Default all)

skip -- Number of logical records to skip (Default 0)

load -- Number of logical records to load (Default all)

errors -- Number of errors to allow (Default 50)

rows -- Number of rows in conventional path bind array or between direct path data saves

(Default: Conventional path 64, Direct path all)

bindsize -- Size of conventional path bind array in bytes (Default 256000)

silent -- Suppress messages during run (header,feedback,errors,discards,partitions)

direct -- use direct path (Default FALSE)

parfile -- parameter file: name of file that contains parameter specifications

parallel -- do parallel load (Default FALSE)

file -- File to allocate extents from skip_unusable_indexes -- disallow/allow unusable indexes or index partitions (Default FALSE) skip_index_maintenance -- do not maintain indexes, mark affected indexes as unusable (Default

FALSE)

readsize -- Size of Read buffer (Default 1048576) external_table -- use external table for load; NOT_USED, GENERATE_ONLY, EXECUTE (Default NOT_

USED) columnarrayrows -- Number of rows for direct path column array (Default 5000) streamsize -- Size of direct path stream buffer in bytes (Default 256000) multithreading -- use multithreading in direct path

resumable -- enable or disable resumable for current session (Default FALSE) resumable_name -- text string to help identify resumable statement resumable_timeout -- wait time (in seconds) for RESUMABLE (Default 7200) date_cache -- size (in entries) of date conversion cache (Default 1000)

PLEASE NOTE: Command-line parameters may be specified either by position or by keywords.

An example of the former case is ’sqlldr scott/tiger foo’; an example of the latter is ’sqlldr control=foo userid=scott/tiger’. One may specify parameters by position before but not after parameters specified by keywords. For example,’sqlldr scott/tiger control=foo logfile=log’ is allowed, but ’sqlldr scott/tiger control=foo log’ is not, even though the position of the parameter ’log’ is correct.

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Command-Line Parameters

Note:

The command to invoke SQL*Loader is operating system-dependent. The examples in this chapter use the

UNIX-based name, sqlldr. See your Oracle operating system-specific documentation for the correct command for your system.

See Also:

Command-Line Parameters on page 4-3 for descriptions of all the command-line parameters

Specifying Parameters in the Control File

If the length of the command line exceeds the size of the maximum command line on your system, you can put some command-line parameters in the control file. See

OPTIONS Clause on page 5-4 for information on how to do this.

They can also be specified in a separate file specified by the PARFILE parameter.

These alternative methods are useful for specifying parameters whose values seldom change. Parameters specified in this manner can be overridden from the command line.

See Also:

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Chapter 5 for a detailed description of the SQL*Loader control file

PARFILE (parameter file) on page 4-10

Command-Line Parameters

This section describes each SQL*Loader command-line parameter. The defaults and maximum values listed for these parameters are for UNIX-based systems. They may be different on your operating system. Refer to your Oracle operating system-specific documentation for more information.

BAD (bad file)

Default: The name of the datafile, with an extension of .bad.

BAD

specifies the name of the bad file created by SQL*Loader to store records that cause errors during insert or that are improperly formatted. If a filename is not specified, the default is used.

SQL*Loader Command-Line Reference

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Command-Line Parameters

A bad file filename specified on the command line becomes the bad file associated with the first INFILE statement in the control file. If the bad file filename was also specified in the control file, the command-line value overrides it.

See Also:

Specifying the Bad File on page 5-11 for information about the format of bad files

BINDSIZE (maximum size)

Default: To see the default value for this parameter, invoke SQL*Loader without any parameters, as described in Invoking SQL*Loader on page 4-1.

BINDSIZE

specifies the maximum size (bytes) of the bind array. The size of the bind array given by BINDSIZE overrides the default size (which is system dependent) and any size determined by ROWS.

See Also:

■

■

Bind Arrays and Conventional Path Loads on page 5-44

READSIZE (read buffer size) on page 4-10

COLUMNARRAYROWS

Default: To see the default value for this parameter, invoke SQL*Loader without any parameters, as described in Invoking SQL*Loader on page 4-1.

Specifies the number of rows to allocate for direct path column arrays. The value for this parameter is not calculated by SQL*Loader. You must either specify it or accept the default.

See Also:

■

■

Using CONCATENATE to Assemble Logical Records on page 5-27

Specifying the Number of Column Array Rows and Size of

Stream Buffers on page 9-21

CONTROL (control file)

Default: none

CONTROL

specifies the name of the SQL*Loader control file that describes how to load data. If a file extension or file type is not specified, it defaults to .ctl. If the filename is omitted, SQL*Loader prompts you for it.

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If the name of your SQL*Loader control file contains special characters, your operating system may require that they be preceded by an escape character. Also, if your operating system uses backslashes in its file system paths, you may need to use multiple escape characters or to enclose the path in quotation marks. See your

Oracle operating system-specific documentation for more information.

See Also:

control file

Chapter 5 for a detailed description of the SQL*Loader

DATA (datafile)

Default: The name of the control file, with an extension of .dat.

DATA

specifies the name of the datafile containing the data to be loaded. If you do not specify a file extension or file type, the default is .dat.

If you specify a datafile on the command line and also specify datafiles in the control file with INFILE, the data specified on the command line is processed first.

The first datafile specified in the control file is ignored. All other datafiles specified in the control file are processed.

If you specify a file processing option when loading data from the control file, a warning message will be issued.

DATE_CACHE

Default: Enabled (for 1000 elements). To completely disable the date cache feature, set it to 0.

DATE_CACHE

specifies the date cache size (in entries). For example, DATE_

CACHE=5000

specifies that each date cache created can contain a maximum of 5000 unique date entries. Every table has its own date cache, if one is needed. A date cache is created only if at least one date or timestamp value is loaded that requires datatype conversion in order to be stored in the table.

The date cache feature is only available for direct path loads. It is enabled by default. The default date cache size is 1000 elements. If the default size is used and the number of unique input values loaded exceeds 1000, then the date cache feature is automatically disabled for that table. However, if you override the default and specify a nonzero date cache size and that size is exceeded, then the cache is not disabled.

You can use the date cache statistics (entries, hits, and misses) contained in the log file to tune the size of the cache for future similar loads.

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See Also:

Specifying a Value for the Date Cache on page 9-22

DIRECT (data path)

Default: false

DIRECT

specifies the data path, that is, the load method to use, either conventional path or direct path. A value of true specifies a direct path load. A value of false specifies a conventional path load.

See Also:

Chapter 9, "Conventional and Direct Path Loads"

DISCARD (filename)

Default: The name of the datafile, with an extension of .dsc.

DISCARD

specifies a discard file (optional) to be created by SQL*Loader to store records that are neither inserted into a table nor rejected.

A discard file filename specified on the command line becomes the discard file associated with the first INFILE statement in the control file. If the discard file filename is specified also in the control file, the command-line value overrides it.

See Also:

Discarded and Rejected Records on page 3-10 for information about the format of discard files

DISCARDMAX (integer)

Default: ALL

DISCARDMAX specifies the number of discard records to allow before data loading is terminated. To stop on the first discarded record, specify one (1).

ERRORS (errors to allow)

Default: To see the default value for this parameter, invoke SQL*Loader without any parameters, as described in Invoking SQL*Loader on page 4-1.

ERRORS

specifies the maximum number of insert errors to allow. If the number of errors exceeds the value specified for ERRORS, then SQL*Loader terminates the load. To permit no errors at all, set ERRORS=0. To specify that all errors be allowed, use a very high number.

On a single-table load, SQL*Loader terminates the load when errors exceed this error limit. Any data inserted up that point, however, is committed.

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SQL*Loader maintains the consistency of records across all tables. Therefore, multitable loads do not terminate immediately if errors exceed the error limit. When

SQL*Loader encounters the maximum number of errors for a multitable load, it continues to load rows to ensure that valid rows previously loaded into tables are loaded into all tables and/or rejected rows filtered out of all tables.

In all cases, SQL*Loader writes erroneous records to the bad file.

EXTERNAL_TABLE

Default: NOT_USED

EXTERNAL_TABLE

instructs SQL*Loader whether or not to load data using the external tables option. There are three possible values:

■

NOT_USED

—the default value. It means the load is performed using either conventional or direct path mode.

■

■

GENERATE_ONLY

—places all the SQL statements needed to do the load using external tables, as described in the control file, in the SQL*Loader log file. These

SQL statements can be edited and customized. The actual load can be done later without the use of SQL*Loader by executing these statements in SQL*Plus. See

Log File Created When EXTERNAL_TABLE=GENERATE_ONLY on page 8-8 for an example of what this log file would look like.

EXECUTE

—attempts to execute the SQL statements that are needed to do the load using external tables. However, if any of the SQL statements returns an error, then the attempt to load stops. Statements are placed in the log file as they are executed. This means that if a SQL statement returns an error, then the remaining SQL statements required for the load will not be placed in the control file.

Note that the external tables option uses directory objects in the database to indicate where all datafiles are stored and to indicate where output files, such as bad files and discard files, are created. You must have READ access to the directory objects containing the datafiles, and you must have WRITE access to the directory objects where the output files are created. If there are no existing directory objects for the location of a datafile or output file, SQL*Loader will generate the SQL statement to create one. Note that if the EXECUTE option is specified, then you must have the

CREATE ANY DIRECTORY

privilege.

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Command-Line Parameters

Note:

The EXTERNAL_TABLE=EXECUTE qualifier tells

SQL*Loader to create an external table that can be used to load data and then execute the INSERT statement to load the data. All files in the external table must be identified as being in a directory object.

SQL*Loader is supposed to use directory objects that already exist and that you have privileges to access. However, SQL*Loader does not find the matching directory object. Because no match is found,

SQL*Loader attempts to create a temporary directory object. If you do not have privileges to create new directory objects, then the operation fails.

To work around this, use EXTERNAL_TABLE=GENERATE_ONLY to create the SQL statements that SQL*Loader would try to execute.

Extract those SQL statements and change references to directory objects to be the directory object that you have privileges to access.

Then, execute those SQL statements

When using a multitable load, SQL*Loader does the following:

1.

Creates a table in the database that describes all fields in the datafile that will be loaded into any table.

2.

Creates an INSERT statement to load this table from an external table description of the data.

3.

Executes one INSERT statement for every table in the control file.

To see an example of this, run case study 5 ( Case Study 5: Loading Data into

Multiple Tables on page 10-18), but add the EXTERNAL_TABLE=GENERATE_ONLY parameter. To guarantee unique names in the external table, SQL*Loader uses generated names for all fields. This is because the field names may not be unique across the different tables in the control file.

See Also:

■

■

Chapter 11, "External Tables Concepts"

Chapter 12, "External Tables Access Parameters"

Restrictions When Using EXTERNAL_TABLE

The following restrictions apply when you use the EXTERNAL_TABLE qualifier:

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■

■

Julian dates cannot be used when you insert data into a database table from an external table through SQL*Loader. To work around this, use TO_DATE and TO_

CHAR

to convert the Julian date format, as shown in the following example:

TO_CHAR(TO_DATE(:COL1, ’MM-DD-YYYY’), ’J’)

Built-in functions and SQL strings cannot be used for object elements when you insert data into a database table from an external table.

FILE (file to load into)

Default: none

FILE

specifies the database file to allocate extents from. It is used only for parallel loads. By varying the value of the FILE parameter for different SQL*Loader processes, data can be loaded onto a system with minimal disk contention.

See Also:

Parallel Data Loading Models on page 9-30

LOAD (records to load)

Default: All records are loaded.

LOAD

specifies the maximum number of logical records to load (after skipping the specified number of records). No error occurs if fewer than the maximum number of records are found.

LOG (log file)

Default: The name of the control file, with an extension of .log.

LOG

specifies the log file that SQL*Loader will create to store logging information about the loading process.

MULTITHREADING

Default: true on multiple-CPU systems, false on single-CPU systems

This parameter is available only for direct path loads.

By default, the multithreading option is always enabled (set to true) on multiple-CPU systems. In this case, the definition of a multiple-CPU system is a single system that has more than one CPU.

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Command-Line Parameters

On single-CPU systems, multithreading is set to false by default. To use multithreading between two single-CPU systems, you must enable multithreading; it will not be on by default. This will allow stream building on the client system to be done in parallel with stream loading on the server system.

Multithreading functionality is operating system-dependent. Not all operating systems support multithreading.

See Also:

Optimizing Direct Path Loads on Multiple-CPU

Systems on page 9-23

PARALLEL (parallel load)

Default: false

PARALLEL

specifies whether direct loads can operate in multiple concurrent sessions to load data into the same table.

See Also:

Parallel Data Loading Models on page 9-30

PARFILE (parameter file)

Default: none

PARFILE

specifies the name of a file that contains commonly used command-line parameters. For example, the command line could read: sqlldr PARFILE=example.par

The parameter file could have the following contents:

USERID=scott/tiger

CONTROL=example.ctl

ERRORS=9999

LOG=example.log

Note:

Although it is not usually important, on some systems it may be necessary to have no spaces around the equal sign (=) in the parameter specifications.

READSIZE (read buffer size)

Default: To see the default value for this parameter, invoke SQL*Loader without any parameters, as described in Invoking SQL*Loader on page 4-1.

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The READSIZE parameter is used only when reading data from datafiles. When reading records from a control file, a value of 64K is always used as the READSIZE.

The READSIZE parameter lets you specify (in bytes) the size of the read buffer, if you choose not to use the default. The maximum size allowed is 20MB for both direct path loads and conventional path loads.

In the conventional path method, the bind array is limited by the size of the read buffer. Therefore, the advantage of a larger read buffer is that more data can be read before a commit is required.

For example: sqlldr scott/tiger CONTROL=ulcas1.ctl READSIZE=1000000

This example enables SQL*Loader to perform reads from the external datafile in chunks of 1,000,000 bytes before a commit is required.

Note:

If the READSIZE value specified is smaller than the

BINDSIZE

value, the READSIZE value will be increased.

The READSIZE parameter has no effect on LOBs. The size of the LOB read buffer is fixed at 64 KB.

See BINDSIZE (maximum size) on page 4-4.

RESUMABLE

Default: false

The RESUMABLE parameter is used to enable and disable resumable space allocation. Because this parameter is disabled by default, you must set

RESUMABLE=true

in order to use its associated parameters, RESUMABLE_NAME and RESUMABLE_TIMEOUT.

See Also:

■

■

Oracle9i Database Concepts

Oracle9i Database Administrator’s Guide

SQL*Loader Command-Line Reference

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Command-Line Parameters

RESUMABLE_NAME

Default: ’User USERNAME (USERID), Session SESSIONID, Instance

INSTANCEID’

The value for this parameter identifies the statement that is resumable. This value is a user-defined text string that is inserted in either the USER_RESUMABLE or DBA_

RESUMABLE

view to help you identify a specific resumable statement that has been suspended.

This parameter is ignored unless the RESUMABLE parameter is set to true to enable resumable space allocation.

RESUMABLE_TIMEOUT

Default: 7200 seconds (2 hours)

The value of the parameter specifies the time period during which an error must be fixed. If the error is not fixed within the timeout period, execution of the statement is aborted.

This parameter is ignored unless the RESUMABLE parameter is set to true to enable resumable space allocation.

ROWS (rows per commit)

Default: To see the default value for this parameter, invoke SQL*Loader without any parameters, as described in Invoking SQL*Loader on page 4-1.

Conventional path loads only: ROWS specifies the number of rows in the bind array.

See Bind Arrays and Conventional Path Loads on page 5-44.

Direct path loads only: ROWS identifies the number of rows you want to read from the datafile before a data save. The default is to read all rows and save data once at the end of the load. See Using Data Saves to Protect Against Data Loss on page 9-13.

Because the direct load is optimized for performance, it uses buffers that are the same size and format as the system’s I/O blocks. Only full buffers are written to the database, so the value of ROWS is approximate.

SILENT (feedback mode)

When SQL*Loader begins, a header message similar to the following appears on the screen and is placed in the log file:

SQL*Loader: Release 9.2.0.1.0 - Production on Wed Feb 27 14:33:54 2002

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(c) Copyright 2002 Oracle Corporation. All rights reserved.

As SQL*Loader executes, you also see feedback messages on the screen, for example:

Commit point reached - logical record count 20

SQL*Loader may also display data error messages like the following:

Record 4: Rejected - Error on table EMP

ORA-00001: unique constraint <name> violated

You can suppress these messages by specifying SILENT with one or more values.

For example, you can suppress the header and feedback messages that normally appear on the screen with the following command-line argument:

SILENT=(HEADER, FEEDBACK)

Use the appropriate values to suppress one or more of the following:

■

HEADER

- Suppresses the SQL*Loader header messages that normally appear on the screen. Header messages still appear in the log file

■

■

■

■

■

FEEDBACK

- Suppresses the "commit point reached" feedback messages that normally appear on the screen

ERRORS

- Suppresses the data error messages in the log file that occur when a record generates an Oracle error that causes it to be written to the bad file. A count of rejected records still appears.

DISCARDS

- Suppresses the messages in the log file for each record written to the discard file.

PARTITIONS

- Disables writing the per-partition statistics to the log file during a direct load of a partitioned table.

ALL

- Implements all of the suppression values: HEADER, FEEDBACK,

ERRORS, DISCARDS,

and PARTITIONS.

SKIP (records to skip)

Default: No records are skipped.

SKIP

specifies the number of logical records from the beginning of the file that should not be loaded.

SQL*Loader Command-Line Reference

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Command-Line Parameters

This parameter continues loads that have been interrupted for some reason. It is used for all conventional loads, for single-table direct loads, and for multiple-table direct loads when the same number of records were loaded into each table. It is not used for multiple-table direct loads when a different number of records were loaded into each table.

See Also:

Interrupted Loads on page 5-24

SKIP_INDEX_MAINTENANCE

Default: false

The SKIP_INDEX_MAINTENANCE parameter stops index maintenance for direct path loads but does not apply to conventional path loads. It causes the index partitions that would have had index keys added to them instead to be marked

Index Unusable because the index segment is inconsistent with respect to the data it indexes. Index segments that are not affected by the load retain the Index Unusable state they had prior to the load.

The SKIP_INDEX_MAINTENANCE parameter:

■

Applies to both local and global indexes

■

Can be used (with the PARALLEL parameter) to do parallel loads on an object that has indexes

■

■

Can be used (with the PARTITION parameter on the INTO TABLE clause) to do a single partition load to a table that has global indexes

Puts a list (in the SQL*Loader log file) of the indexes and index partitions that the load set into Index Unusable state

SKIP_UNUSABLE_INDEXES

Default: false

The SKIP_UNUSABLE_INDEXES parameter applies to both conventional and direct path loads.

SKIP_UNUSABLE_INDEXES=true

allows SQL*Loader to load a table with indexes that are in Index Unusable (IU) state prior to the beginning of the load. Indexes that are not in IU state at load time will be maintained by SQL*Loader. Indexes that are in IU state at load time will not be maintained but will remain in IU state at load completion.

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However, indexes that are unique and marked IU are not allowed to skip index maintenance. This rule is enforced by DML operations, and enforced by the direct path load to be consistent with DML.

Load behavior with SKIP_UNUSABLE_INDEXES=false differs slightly between conventional path loads and direct path loads:

■

On a conventional path load, records that are to be inserted will instead be rejected if their insertions would require updating an index.

■

On a direct path load, the load terminates upon encountering a record that would require index maintenance be done on an index that is in unusable state.

STREAMSIZE

Default: To see the default value for this parameter, invoke SQL*Loader without any parameters, as described in Invoking SQL*Loader on page 4-1.

Specifies the size, in bytes, for direct path streams.

See Also:

Specifying the Number of Column Array Rows and

Size of Stream Buffers on page 9-21

USERID (username/password)

Default: none

USERID is used to provide your Oracle username/password. If it is omitted, you are prompted for it. If only a slash is used, USERID defaults to your operating system login.

If you connect as user SYS, you must also specify AS SYSDBA in the connect string.

For example: sqlldr \’SYS/ password AS SYSDBA\’ foo.ctl

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Exit Codes for Inspection and Display

Note:

This example shows the entire connect string enclosed in quotation marks and backslashes. This is because the string, AS

SYSDBA,

contains a blank, a situation for which most operating systems require that the entire connect string be placed in quotation marks or marked as a literal by some method. Some operating systems also require that quotation marks on the command line be preceded by an escape character. In this example, backslashes are used as the escape character. If the backslashes were not present, the command line parser that SQL*Loader uses would not understand the quotation marks and would remove them.

See your Oracle operating system-specific documentation for information about special and reserved characters on your system.

Exit Codes for Inspection and Display

Oracle SQL*Loader provides the results of a SQL*Loader run immediately upon completion. Depending on the platform, SQL*Loader may report the outcome in a process exit code as well as recording the results in the log file. This Oracle

SQL*Loader functionality allows for checking the outcome of a SQL*Loader invocation from the command line or script.

Table 4–1 shows the exit codes for various results.

Table 4–1 Exit Codes for SQL*Loader

Result

All rows loaded successfully

All or some rows rejected

All or some rows discarded

Discontinued load

Command-line or syntax errors

Oracle errors nonrecoverable for SQL*Loader

Operating system errors (such as file open/close and malloc)

Exit Code

EX_SUCC

EX_WARN

EX_WARN

EX_WARN

EX_FAIL

EX_FAIL

EX_FAIL

For UNIX, the exit codes are as follows:

EX_SUCC 0

EX_FAIL 1

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EX_WARN 2

EX_FTL 3

For Windows NT, the exit codes are as follows:

EX_SUCC 0

EX_WARN 2

EX_FAIL 3

EX_FTL 4

If SQL*Loader returns any exit code other than zero, you should consult your system log files and SQL*Loader log files for more detailed diagnostic information.

In UNIX, you can check the exit code from the shell to determine the outcome of a load. For example, you could place the SQL*Loader command in a script and check the exit code within the script:

#!/bin/sh sqlldr scott/tiger control=ulcase1.ctl log=ulcase1.log

retcode=`echo $?` case "$retcode" in

0) echo "SQL*Loader execution successful" ;;

1) echo "SQL*Loader execution exited with EX_FAIL, see logfile" ;;

2) echo "SQL*Loader execution exited with EX_WARN, see logfile" ;;

3) echo "SQL*Loader execution encountered a fatal error" ;;

*) echo "unknown return code";; esac

SQL*Loader Command-Line Reference

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Exit Codes for Inspection and Display

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5

SQL*Loader Control File Reference

This chapter describes the SQL*Loader control file. The following topics are included:

■

■

Control File Contents

Specifying Command-Line Parameters in the Control File

■

■

■

■

Specifying Filenames and Object Names

Specifying Datafiles

Identifying Data in the Control File with BEGINDATA

Specifying Datafile Format and Buffering

■

■

■

■

■

■

■

■

■

Specifying the Bad File

Specifying the Discard File

Handling Different Character Encoding Schemes

Interrupted Loads

Assembling Logical Records from Physical Records

Loading Logical Records into Tables

Index Options

Benefits of Using Multiple INTO TABLE Clauses

Bind Arrays and Conventional Path Loads

SQL*Loader Control File Reference

5-1

Control File Contents

Control File Contents

The SQL*Loader control file is a text file that contains data definition language

(DDL) instructions. DDL is used to control the following aspects of a SQL*Loader session:

■

■

■

■

Where SQL*Loader will find the data to load

How SQL*Loader expects that data to be formatted

How SQL*Loader will be configured (memory management, rejecting records, interrupted load handling, and so on) as it loads the data

How SQL*Loader will manipulate the data being loaded

See Appendix A for syntax diagrams of the SQL*Loader DDL.

To create the SQL*Loader control file, use a text editor such as vi or xemacs.create.

In general, the control file has three main sections, in the following order:

■

Session-wide information

■

■

Table and field-list information

Input data (optional section)

Example 5–1 shows a sample control file.

Example 5–1 Sample Control File

1

-- This is a sample control file

2

LOAD DATA

3

INFILE ’sample.dat’

4

BADFILE ’sample.bad’

5

DISCARDFILE ’sample.dsc’

6

APPEND

7

INTO TABLE emp

8

WHEN (57) = ’.’

9

TRAILING NULLCOLS

10

(hiredate SYSDATE,

deptno POSITION(1:2) INTEGER EXTERNAL(2)

NULLIF deptno=BLANKS,

job POSITION(7:14) CHAR TERMINATED BY WHITESPACE

NULLIF job=BLANKS "UPPER(:job)",

mgr POSITION(28:31) INTEGER EXTERNAL

TERMINATED BY WHITESPACE, NULLIF mgr=BLANKS,

ename POSITION(34:41) CHAR

TERMINATED BY WHITESPACE "UPPER(:ename)",

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empno POSITION(45) INTEGER EXTERNAL

TERMINATED BY WHITESPACE,

sal POSITION(51) CHAR TERMINATED BY WHITESPACE

"TO_NUMBER(:sal,’$99,999.99’)",

comm INTEGER EXTERNAL ENCLOSED BY ’(’ AND ’%’

":comm * 100"

)

In this sample control file, the numbers that appear to the left would not appear in a real control file. They are keyed in this sample to the explanatory notes in the following list:

1.

This is how comments are entered in a control file. See Comments in the

Control File on page 5-4.

2.

3.

4.

5.

The LOAD DATA statement tells SQL*Loader that this is the beginning of a new data load. See Appendix A for syntax information.

The INFILE clause specifies the name of a datafile containing data that you want to load. See Specifying Datafiles on page 5-7.

The BADFILE parameter specifies the name of a file into which rejected records are placed. See Specifying the Bad File on page 5-11.

The DISCARDFILE parameter specifies the name of a file into which discarded records are placed. See Specifying the Discard File on page 5-14.

6.

7.

8.

9.

The APPEND parameter is one of the options you can use when loading data into a table that is not empty. See Loading Data into Nonempty Tables on page 5-33.

To load data into a table that is empty, you would use the INSERT parameter.

See Loading Data into Empty Tables on page 5-33.

The INTO TABLE clause allows you to identify tables, fields, and datatypes. It defines the relationship between records in the datafile and tables in the database. See Specifying Table Names on page 5-32.

The WHEN clause specifies one or more field conditions. SQL*Loader decides whether or not to load the data based on these field conditions. See Loading

Records Based on a Condition on page 5-35.

The TRAILING NULLCOLS clause tells SQL*Loader to treat any relatively positioned columns that are not present in the record as null columns. See

Handling Short Records with Missing Data on page 5-37.

SQL*Loader Control File Reference

5-3

Specifying Command-Line Parameters in the Control File

10.

The remainder of the control file contains the field list, which provides information about column formats in the table being loaded. See Chapter 6 for information about that section of the control file.

Comments in the Control File

Comments can appear anywhere in the command section of the file, but they should not appear within the data. Precede any comment with two hyphens, for example:

--This is a comment

All text to the right of the double hyphen is ignored, until the end of the line. An example of comments in a control file is shown in Case Study 3: Loading a

Delimited, Free-Format File on page 10-11.

Specifying Command-Line Parameters in the Control File

The OPTIONS clause is useful when you typically invoke a control file with the same set of options. The OPTIONS clause precedes the LOAD DATA statement.

OPTIONS Clause

The OPTIONS clause allows you to specify runtime parameters in the control file, rather than on the command line. The following parameters can be specified using the OPTIONS clause. These parameters are described in greater detail in Chapter 4 .

BINDSIZE = n

COLUMNARRAYROWS = n

DIRECT = {TRUE | FALSE}

ERRORS = n

LOAD = n

MULTITHREADING = {TRUE | FALSE}

PARALLEL = {TRUE | FALSE}

READSIZE = n

RESUMABLE = {TRUE | FALSE}

RESUMABLE_NAME = ’text string’

RESUMABLE_TIMEOUT = n

ROWS =

n

SILENT = {HEADERS | FEEDBACK | ERRORS | DISCARDS | PARTITIONS | ALL}

SKIP = n

SKIP_INDEX_MAINTENANCE = {TRUE | FALSE}

SKIP_UNUSABLE_INDEXES = {TRUE | FALSE}

STREAMSIZE = n

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For example:

OPTIONS (BINDSIZE=100000, SILENT=(ERRORS, FEEDBACK) )

Note:

Values specified on the command line override values specified in the OPTIONS clause in the control file.

Specifying Filenames and Object Names

In general, SQL*Loader follows the SQL standard for specifying object names (for example, table and column names). The information in this section discusses the following topics:

■

■

■

Filenames That Conflict with SQL and SQL*Loader Reserved Words

Specifying SQL Strings

Operating System Considerations

Filenames That Conflict with SQL and SQL*Loader Reserved Words

SQL and SQL*Loader reserved words must be specified within double quotation marks. The only SQL*Loader reserved word is CONSTANT.

You must use double quotation marks if the object name contains special characters other than those recognized by SQL ($, #, _), or if the name is case sensitive.

See Also:

Oracle9i SQL Reference

Specifying SQL Strings

You must specify SQL strings within double quotation marks. The SQL string applies SQL operators to data fields.

See Also:

Applying SQL Operators to Fields on page 6-50

Operating System Considerations

The following sections discuss situations in which your course of action may depend on the operating system you are using.

SQL*Loader Control File Reference

5-5

Specifying Filenames and Object Names

Specifying a Complete Path

If you encounter problems when trying to specify a complete path name, it may be due to an operating system-specific incompatibility caused by special characters in the specification. In many cases, specifying the path name within single quotation marks prevents errors.

If not, please see your Oracle operating system-specific documentation for possible solutions.

Backslash Escape Character

In DDL syntax, you can place a double quotation mark inside a string delimited by double quotation marks by preceding it with the escape character, "\" (if the escape character is allowed on your operating system). The same rule applies when single quotation marks are required in a string delimited by single quotation marks.

For example, homedir\data"norm\mydata

contains a double quotation mark.

Preceding the double quotation mark with a backslash indicates that the double quotation mark is to be taken literally:

INFILE ’homedir\data\"norm\mydata’

You can also put the escape character itself into a string by entering it twice:

For example:

"so’\"far" or ’so\’"far’ is parsed as so’"far

"’so\\far’" or ’\’so\\far\’’ is parsed as ’so\far’

"so\\\\far" or ’so\\\\far’ is parsed as so\\far

Note:

A double quotation mark in the initial position cannot be preceded by an escape character. Therefore, you should avoid creating strings with an initial quotation mark.

Nonportable Strings

There are two kinds of character strings in a SQL*Loader control file that are not portable between operating systems: filename and file processing option strings. When you convert to a different operating system, you will probably need to modify these strings. All other strings in a SQL*Loader control file should be portable between operating systems.

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Escaping the Backslash

If your operating system uses the backslash character to separate directories in a path name, and if the version of the Oracle database server running on your operating system implements the backslash escape character for filenames and other nonportable strings, then you must specify double backslashes in your path names and use single quotation marks.

See your Oracle operating system-specific documentation for information about which escape characters are required or allowed.

Escape Character Is Sometimes Disallowed

The version of the Oracle database server running on your operating system may not implement the escape character for nonportable strings. When the escape character is disallowed, a backslash is treated as a normal character, rather than as an escape character (although it is still usable in all other strings). Then path names such as the following can be specified normally:

INFILE ’topdir\mydir\myfile’

Double backslashes are not needed.

Because the backslash is not recognized as an escape character, strings within single quotation marks cannot be embedded inside another string delimited by single quotation marks. This rule also holds for double quotation marks. A string within double quotation marks cannot be embedded inside another string delimited by double quotation marks.

Specifying Datafiles

To specify a datafile that contains the data to be loaded, use the INFILE clause, followed by the filename and optional file processing options string. You can specify multiple files by using multiple INFILE clauses.

Note:

You can also specify the datafile from the command line, using the DATA parameter described in Command-Line Parameters on page 4-3. A filename specified on the command line overrides the first INFILE clause in the control file.

If no filename is specified, the filename defaults to the control filename with an extension or file type of .dat.

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Specifying Datafiles

INFILE

INDDN

If the control file itself contains the data to be loaded, specify an asterisk (*). This specification is described in Identifying Data in the Control File with BEGINDATA on page 5-10.

Note:

The information in this section applies only to primary datafiles. It does not apply to LOBFILEs or SDFs.

For information about LOBFILES, see Loading LOB Data from

LOBFILEs on page 7-23.

For information about SDFs, see Secondary Datafiles (SDFs) on page 7-31.

The syntax for the INFILE clause is as follows: os_file_proc_clause

BADFILE

BADDN filename

* input_filename

DISCARDFILE

DISCARDDN filename

DISCARDS

DISCARDMAX integer

Table 5–1 describes the parameters for the INFILE clause.

Table 5–1 Parameters for the INFILE Clause

Parameter

INFILE

or INDDN input_filename

Description

Specifies that a datafile specification follows.

Note that INDDN has been retained for situations in which compatibility with DB2 is required.

Name of the file containing the data.

Any spaces or punctuation marks in the filename must be enclosed in single quotation marks. See Specifying Filenames and Object Names on page 5-5.

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Table 5–1 (Cont.) Parameters for the INFILE Clause

Parameter Description

* If your data is in the control file itself, use an asterisk instead of the filename. If you have data in the control file as well as datafiles, you must specify the asterisk first in order for the data to be read.

os_file_proc_clause

This is the file-processing options string. It specifies the datafile format. It also optimizes datafile reads. The syntax used for this string is specific to your operating system. See Specifying

Datafile Format and Buffering on page 5-11.

Examples of INFILE Syntax

The following list shows different ways you can specify INFILE syntax:

■

Data contained in the control file itself:

INFILE *

■

■

Data contained in a file named foo with a default extension of .dat:

INFILE foo

Data contained in a file named datafile.dat with a full path specified:

INFILE ’c:/topdir/subdir/datafile.dat’

Note:

Filenames that include spaces or punctuation marks must be enclosed in single quotation marks. For more details on filename specification, see Specifying Filenames and Object Names on page 5-5.

Specifying Multiple Datafiles

To load data from multiple datafiles in one SQL*Loader run, use an INFILE statement for each datafile. Datafiles need not have the same file processing options, although the layout of the records must be identical. For example, two files could be specified with completely different file processing options strings, and a third could consist of data in the control file.

You can also specify a separate discard file and bad file for each datafile. In such a case, the separate bad files and discard files must be declared immediately after

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5-9

Identifying Data in the Control File with BEGINDATA each datafile name. For example, the following excerpt from a control file specifies four datafiles with separate bad and discard files:

INFILE mydat1.dat BADFILE mydat1.bad DISCARDFILE mydat1.dis

INFILE mydat2.dat

INFILE mydat3.dat DISCARDFILE mydat3.dis

INFILE mydat4.dat DISCARDMAX 10 0

■

■

■

■

For mydat1.dat, both a bad file and discard file are explicitly specified.

Therefore both files are created, as needed.

For mydat2.dat, neither a bad file nor a discard file is specified. Therefore, only the bad file is created, as needed. If created, the bad file has the default filename and extension mydat2.bad. The discard file is not created, even if rows are discarded.

For mydat3.dat, the default bad file is created, if needed. A discard file with the specified name (mydat3.dis) is created, as needed.

For mydat4.dat, the default bad file is created, if needed. Because the

DISCARDMAX option is used, SQL*Loader assumes that a discard file is required and creates it with the default name mydat4.dsc.

Identifying Data in the Control File with BEGINDATA

If the data is included in the control file itself, then the INFILE clause is followed by an asterisk rather than a filename. The actual data is placed in the control file after the load configuration specifications.

Specify the BEGINDATA parameter before the first data record. The syntax is:

BEGINDATA data

Keep the following points in mind when using the BEGINDATA parameter:

■

■

If you omit the BEGINDATA parameter but include data in the control file,

SQL*Loader tries to interpret your data as control information and issues an error message. If your data is in a separate file, do not use the BEGINDATA parameter.

Do not use spaces or other characters on the same line as the BEGINDATA parameter, or the line containing BEGINDATA will be interpreted as the first line of data.

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■

Do not put comments after BEGINDATA, or they will also be interpreted as data.

See Also:

■

Specifying Datafiles on page 5-7 for an explanation of using

INFILE

■

Case Study 1: Loading Variable-Length Data on page 10-5

Specifying Datafile Format and Buffering

When configuring SQL*Loader, you can specify an operating system-dependent file processing options string (os_file_proc_clause) in the control file to specify file format and buffering.

For example, suppose that your operating system has the following option-string syntax:

RECSIZE integer BUFFERS integer

In this syntax, RECSIZE is the size of a fixed-length record, and BUFFERS is the number of buffers to use for asynchronous I/O.

To declare a file named mydata.dat as a file that contains 80-byte records and instruct SQL*Loader to use 8 I/O buffers, you would use the following control file entry:

INFILE ’mydata.dat’ "RECSIZE 80 BUFFERS 8"

For details on the syntax of the file processing options string, see your Oracle operating system-specific documentation.

Note:

This example uses the recommended convention of single quotation marks for filenames and double quotation marks for everything else.

Specifying the Bad File

When SQL*Loader executes, it can create a file called a bad file or reject file in which it places records that were rejected because of formatting errors or because they

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Specifying the Bad File caused Oracle errors. If you have specified that a bad file is to be created, the following applies:

■

If one or more records are rejected, the bad file is created and the rejected records are logged.

■

■

If no records are rejected, then the bad file is not created. When this occurs, you must reinitialize the bad file for the next run.

If the bad file is created, it overwrites any existing file with the same name; ensure that you do not overwrite a file you wish to retain.

Note:

On some systems, a new version of the file is created if a file with the same name already exists. See your Oracle operating system-specific documentation to find out if this is the case on your system.

To specify the name of the bad file, use the BADFILE parameter (or BADDN for DB2 compatibility), followed by the bad file filename. If you do not specify a name for the bad file, the name defaults to the name of the datafile with an extension or file type of .bad. You can also specify the bad file from the command line with the

BAD

parameter described in Command-Line Parameters on page 4-3.

A filename specified on the command line is associated with the first INFILE or

INDDN

clause in the control file, overriding any bad file that may have been specified as part of that clause.

The bad file is created in the same record and file format as the datafile so that the data can be reloaded after making corrections. For datafiles in stream record format, the record terminator that is found in the datafile is also used in the bad file.

The syntax for the bad file is as follows:

BADFILE

BADDN bad_filename

The BADFILE or BADDN parameter specifies that a filename for the bad file follows.

(Use BADDN when DB2 compatibility is required.)

The bad_filename parameter specifies a valid filename specification for your platform. Any spaces or punctuation marks in the filename must be enclosed in single quotation marks.

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Examples of Specifying a Bad File Name

To specify a bad file with filename foo and default file extension or file type of

.bad,

enter:

BADFILE foo

To specify a bad file with filename bad0001 and file extension or file type of .rej, enter either of the following lines:

BADFILE bad0001.rej

BADFILE ’/REJECT_DIR/bad0001.rej’

How Bad Files Are Handled with LOBFILEs and SDFs

Data from LOBFILEs and SDFs is not written to a bad file when there are rejected rows. If there is an error loading a LOB, the row is not rejected. Rather, the LOB column is left empty (not null with a length of zero (0) bytes). However, when the

LOBFILE is being used to load an XML column and there is an error loading this

LOB data, then the XML column is left as null.

Criteria for Rejected Records

A record can be rejected for the following reasons:

1.

2.

3.

Upon insertion, the record causes an Oracle error (such as invalid data for a given datatype).

The record is formatted incorrectly so that SQL*Loader cannot find field boundaries.

The record violates a constraint or tries to make a unique index non-unique.

If the data can be evaluated according to the WHEN clause criteria (even with unbalanced delimiters), then it is either inserted or rejected.

Neither a conventional path nor a direct path load will write a row to any table if it is rejected because of reason number 2 in the previous list.

Additionally, a conventional path load will not write a row to any tables if reason number 1 or 3 in the previous list is violated for any one table. The row is rejected for that table and written to the reject file.

The log file indicates the Oracle error for each rejected record.

Case Study 4:

Loading Combined Physical Records on page 10-14 demonstrates rejected records.

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Specifying the Discard File

Specifying the Discard File

During SQL*Loader execution, it can create a discard file for records that do not meet any of the loading criteria. The records contained in this file are called discarded records. Discarded records do not satisfy any of the WHEN clauses specified in the control file. These records differ from rejected records. Discarded

records do not necessarily have any bad data. No insert is attempted on a discarded record.

A discard file is created according to the following rules:

■

■

You have specified a discard filename and one or more records fail to satisfy all of the WHEN clauses specified in the control file. (If the discard file is created, it overwrites any existing file with the same name, so be sure that you do not overwrite any files you wish to retain.)

If no records are discarded, then a discard file is not created.

To create a discard file from within a control file, specify any of the following:

DISCARDFILE filename

, DISCARDDN filename (DB2), DISCARDS, or

DISCARDMAX

.

To create a discard file from the command line, specify either DISCARD or

DISCARDMAX

.

You can specify the discard file directly by specifying its name, or indirectly by specifying the maximum number of discards.

The discard file is created in the same record and file format as the datafile. For datafiles in stream record format, the same record terminator that is found in the datafile is also used in the discard file.

Specifying the Discard File in the Control File

To specify the name of the file, use the DISCARDFILE or DISCARDDN (for

DB2-compatibility) parameter, followed by the filename.

DISCARDFILE

DISCARDDN discard_filename

DISCARDS

DISCARDMAX integer

The DISCARDFILE or DISCARDDN parameter specifies that a discard filename follows. (Use DISCARDDN when DB2 compatibility is required.)

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The discard_filename parameter specifies a valid filename specification for your platform. Any spaces or punctuation marks in the filename must be enclosed in single quotation marks.

The default filename is the name of the datafile, and the default file extension or file type is .dsc. A discard filename specified on the command line overrides one specified in the control file. If a discard file with that name already exists, it is either overwritten or a new version is created, depending on your operating system.

Specifying the Discard File from the Command Line

See DISCARD (filename) on page 4-6 for information on how to specify a discard file from the command line.

A filename specified on the command line overrides any discard file that you may have specified in the control file.

Examples of Specifying a Discard File Name

The following list shows different ways you can specify a name for the discard file from within the control file:

■

To specify a discard file with filename circular and default file extension or file type of .dsc:

DISCARDFILE circular

■

To specify a discard file named notappl with the file extension or file type of

.may:

DISCARDFILE notappl.may

■

To specify a full path to the discard file forget.me:

DISCARDFILE ’/discard_dir/forget.me’

Criteria for Discarded Records

If there is no INTO TABLE clause specified for a record, the record is discarded.

This situation occurs when every INTO TABLE clause in the SQL*Loader control file has a WHEN clause and, either the record fails to match any of them, or all fields are null.

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Handling Different Character Encoding Schemes

No records are discarded if an INTO TABLE clause is specified without a WHEN clause. An attempt is made to insert every record into such a table. Therefore, records may be rejected, but none are discarded.

Case Study 7: Extracting Data from a Formatted Report on page 10-28 provides an example of using a discard file.

How Discard Files Are Handled with LOBFILEs and SDFs

Data from LOBFILEs and SDFs is not written to a discard file when there are discarded rows.

Limiting the Number of Discarded Records

You can limit the number of records to be discarded for each datafile by specifying an integer:

DISCARDS

DISCARDMAX integer

When the discard limit (specified with integer) is reached, processing of the datafile terminates and continues with the next datafile, if one exists.

You can specify a different number of discards for each datafile. Or, if you specify the number of discards only once, then the maximum number of discards specified applies to all files.

If you specify a maximum number of discards, but no discard filename,

SQL*Loader creates a discard file with the default filename and file extension or file type.

Handling Different Character Encoding Schemes

SQL*Loader supports different character encoding schemes (called character sets, or code pages). SQL*Loader uses features of Oracle’s globalization support technology to handle the various single-byte and multibyte character encoding schemes available today.

See Also:

Oracle9i Database Globalization Support Guide

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In general, loading shift-sensitive character data can be much slower than loading simple ASCII or EBCDIC data. The fastest way to load shift-sensitive character data is to use fixed-position fields without delimiters. To improve performance, remember the following points:

■

■

The field data must have an equal number of shift-out/shift-in bytes.

The field must start and end in single-byte mode.

■

■

It is acceptable for the first byte to be shift-out and the last byte to be shift-in.

The first and last characters cannot be multibyte.

■

If blanks are not preserved and multibyte-blank-checking is required, a slower path is used. This can happen when the shift-in byte is the last byte of a field after single-byte blank stripping is performed.

The following sections provide a brief introduction to some of the supported character encoding schemes.

Multibyte (Asian) Character Sets

Multibyte character sets support Asian languages. Data can be loaded in multibyte format, and database object names (fields, tables, and so on) can be specified with multibyte characters. In the control file, comments and object names can also use multibyte characters.

Unicode Character Sets

SQL*Loader supports loading data that is in a Unicode character set.

Unicode is a universal encoded character set that supports storage of information from most languages in a single character set. Unicode provides a unique code value for every character, regardless of the platform, program, or language. There are two different encodings for Unicode, UTF-16 and UTF-8.

Note:

In this manual, you will see the terms UTF-16 and UTF16 both used. The term UTF-16 is a general reference to UTF-16 encoding for Unicode. The term UTF16 (no hyphen) is the specific name of the character set and is what you should specify for the

CHARACTERSET

parameter when you want to use UTF-16 encoding. This also applies to UTF-8 and UTF8.

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The UTF-16 Unicode encoding is a fixed-width multibyte encoding in which the character codes 0x0000 through 0x007F have the same meaning as the single-byte

ASCII codes 0x00 through 0x7F.

The UTF-8 Unicode encoding is a variable-width multibyte encoding in which the character codes 0x00 through 0x7F have the same meaning as ASCII. A character in

UTF-8 can be 1 byte, 2 bytes, or 3 bytes long.

See Also:

■

■

Case Study 11: Loading Data in the Unicode Character Set on page 10-47

Oracle9i Database Globalization Support Guide for more information on Unicode encoding.

Database Character Sets

The Oracle database server uses the database character set for data stored in SQL

CHAR

datatypes (CHAR, VARCHAR2, CLOB, and LONG), for identifiers such as table names, and for SQL statements and PL/SQL source code. Only single-byte character sets and varying-width character sets that include either ASCII or

EBCDIC characters are supported as database character sets. Multibyte fixed-width character sets (for example, AL16UTF16) are not supported as the database character set.

An alternative character set can be used in the database for data stored in SQL

NCHAR datatypes (NCHAR, NVARCHAR, and NCLOB). This alternative character set is called the database national character set. Only Unicode character sets are supported as the database national character set.

Datafile Character Sets

By default, the datafile is in the character set as defined by the NLS_LANG parameter. The datafile character sets supported with NLS_LANG are the same as those supported as database character sets. SQL*Loader supports all

Oracle-supported character sets in the datafile (even those not supported as database character sets).

For example, SQL*Loader supports multibyte fixed-width character sets (such as

AL16UTF16 and JA16EUCFIXED) in the datafile. SQL*Loader also supports UTF-16 encoding with little endian byte ordering. However, the Oracle database server supports only UTF-16 encoding with big endian byte ordering (AL16UTF16) and only as a database national character set, not as a database character set.

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The character set of the datafile can be set up by using the NLS_LANG parameter or by specifying a SQL*Loader CHARACTERSET parameter.

Input Character Conversion

The default character set for all datafiles, if the CHARACTERSET parameter is not specified, is the session character set defined by the NLS_LANG parameter. The character set used in input datafiles can be specified with the CHARACTERSET parameter.

SQL*Loader has the capacity to automatically convert data from the datafile character set to the database character set or the database national character set, when they differ.

When data character set conversion is required, the target character set should be a superset of the source datafile character set. Otherwise, characters that have no equivalent in the target character set are converted to replacement characters, often a default character such as a question mark (?). This causes loss of data.

The sizes of the database character types CHAR and VARCHAR2 can be specified in bytes (byte-length semantics) or in characters (character-length semantics). If they are specified in bytes, and data character set conversion is required, the converted values may take more bytes than the source values if the target character set uses more bytes than the source character set for any character that is converted. This will result in the following error message being reported if the larger target value exceeds the size of the database column:

ORA-01401: inserted value too large for column

You can avoid this problem by specifying the database column size in characters and by also using character sizes in the control file to describe the data. Another way to avoid this problem is to ensure that the maximum column size is large enough, in bytes, to hold the converted value.

See Also:

■

■

Oracle9i Database Concepts for more information about character-length semantics in the database.

Character-Length Semantics on page 5-22

CHARACTERSET Parameter

Specifying the CHARACTERSET parameter tells SQL*Loader the character set of the input datafile. The default character set for all datafiles, if the CHARACTERSET

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Handling Different Character Encoding Schemes parameter is not specified, is the session character set defined by the NLS_LANG parameter. Only character data (fields in the SQL*Loader datatypes CHAR,

VARCHAR, VARCHARC,

numeric EXTERNAL, and the datetime and interval datatypes) is affected by the character set of the datafile.

The CHARACTERSET syntax is as follows:

CHARACTERSET char_set_name

The char_set_name variable specifies the character set name. Normally, the specified name must be the name of an Oracle-supported character set.

For UTF-16 Unicode encoding, use the name UTF16 rather than AL16UTF16.

AL16UTF16, which is the supported Oracle character set name for UTF-16 encoded data, is only for UTF-16 data that is in big endian byte order. However, because you are allowed to set up data using the byte order of the system where you create the datafile, the data in the datafile can be either big endian or little endian. Therefore, a different character set name (UTF16) is used. The character set name AL16UTF16 is also supported. But if you specify AL16UTF16 for a datafile that has little endian byte order, SQL*Loader issues a warning message and processes the datafile as big endian.

The CHARACTERSET parameter can be specified for primary datafiles as well as

LOBFILEs and SDFs. It is possible to specify different character sets for different input datafiles. A CHARACTERSET parameter specified before the INFILE parameter applies to the entire list of primary datafiles. If the CHARACTERSET parameter is specified for primary datafiles, the specified value will also be used as the default for LOBFILEs and SDFs. This default setting can be overridden by specifying the CHARACTERSET parameter with the LOBFILE or SDF specification.

The character set specified with the CHARACTERSET parameter does not apply to data in the control file (specified with INFILE). To load data in a character set other than the one specified for your session by the NLS_LANG parameter, you must place the data in a separate datafile.

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See Also:

■

Byte Ordering on page 6-37

■

■

■

Oracle9i Database Globalization Support Guide for more information on the names of the supported character sets

Control File Character Set on page 5-21

Case Study 11: Loading Data in the Unicode Character Set on page 10-47 for an example of loading a datafile that contains little endian UTF-16 encoded data

Control File Character Set

The SQL*Loader control file itself is assumed to be in the character set specified for your session by the NLS_LANG parameter. If the control file character set is different from the datafile character set, keep the following issue in mind. Delimiters and comparison clause values specified in the SQL*Loader control file as character strings are converted from the control file character set to the datafile character set before any comparisons are made. To ensure that the specifications are correct, you may prefer to specify hexadecimal strings, rather than character string values.

If hexadecimal strings are used with a datafile in the UTF-16 Unicode encoding, the byte order is different on a big endian versus a little endian system. For example, ","

(comma) in UTF-16 on a big endian system is X’002c’. On a little endian system it is

X’2c00’. SQL*Loader requires that you always specify hexadecimal strings in big endian format. If necessary, SQL*Loader swaps the bytes before making comparisons. This allows the same syntax to be used in the control file on both a big endian and a little endian system.

Record terminators for datafiles that are in stream format in the UTF-16 Unicode encoding default to "\n" in UTF-16 (that is, 0x000A on a big endian system and

0x0A00 on a little endian system). You can override these default settings by using the "STR ’char_str’" or the "STR x’hex_str’" specification on the INFILE line. For example, you could use either of the following to specify that ’ab’ is to be used as the record terminator, instead of ’\n’.

INFILE myfile.dat "STR ’ab’"

INFILE myfile.dat "STR x’00410042’"

Any data included after the BEGINDATA statement is also assumed to be in the character set specified for your session by the NLS_LANG parameter.

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Handling Different Character Encoding Schemes

For the SQL*Loader datatypes (CHAR, VARCHAR, VARCHARC, DATE, and

EXTERNAL

numerics), SQL*Loader supports lengths of character fields that are specified in either bytes (byte-length semantics) or characters (character-length semantics). For example, the specification CHAR(10) in the control file can mean 10 bytes or 10 characters. These are equivalent if the datafile uses a single-byte character set. However, they are often different if the datafile uses a multibyte character set.

To avoid insertion errors caused by expansion of character strings during character set conversion, use character-length semantics in both the datafile and the target database columns.

Character-Length Semantics

Byte-length semantics are the default for all datafiles except those that use the

UTF16 character set (which uses character-length semantics by default). To override the default you can specify CHAR or CHARACTER, as shown in the following syntax:

LENGTH

SEMANTICS

BYTE

CHAR

CHARACTER

The LENGTH parameter is placed after the CHARACTERSET parameter in the

SQL*Loader control file. The LENGTH parameter applies to the syntax specification for primary datafiles as well as to LOBFILEs and secondary datafiles (SDFs). It is possible to specify different length semantics for different input datafiles. However, a LENGTH specification before the INFILE parameters applies to the entire list of primary datafiles. The LENGTH specification specified for the primary datafile is used as the default for LOBFILEs and SDFs. You can override that default by specifying LENGTH with the LOBFILE or SDF specification. Unlike the

CHARACTERSET parameter, the LENGTH parameter can also apply to data contained within the control file itself (that is, INFILE * syntax).

You can specify CHARACTER instead of CHAR for the LENGTH parameter.

If character-length semantics are being used for a SQL*Loader datafile, then the following SQL*Loader datatypes will use character-length semantics:

■

CHAR

■

VARCHAR

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■

■

VARCHARC

■

DATE

■

EXTERNAL numerics (INTEGER, FLOAT, DECIMAL, and ZONED)

For the VARCHAR datatype, the length subfield is still a binary SMALLINT length subfield, but its value indicates the length of the character string in characters.

The following datatypes use byte-length semantics even if character-length semantics are being used for the datafile, because the data is binary, or is in a special binary-encoded form in the case of ZONED and DECIMAL:

■

INTEGER

SMALLINT

■

FLOAT

■

■

DOUBLE

BYTEINT

■

■

ZONED

DECIMAL

■

RAW

VARRAW

■

■

VARRAWC

GRAPHIC

■

■

GRAPHIC EXTERNAL

■

VARGRAPHIC

The start and end arguments to the POSITION parameter are interpreted in bytes, even if character-length semantics are in use in a datafile. This is necessary to handle datafiles that have a mix of data of different datatypes, some of which use character-length semantics, and some of which use byte-length semantics. It is also needed to handle position with the VARCHAR datatype, which has a SMALLINT length field and then the character data. The SMALLINT length field takes up a certain number of bytes depending on the system (usually 2 bytes), but its value indicates the length of the character string in characters.

Character-length semantics in the datafile can be used independent of whether or not character-length semantics are used for the database columns. Therefore, the

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5-23

Interrupted Loads datafile and the database columns can use either the same or different length semantics.

Interrupted Loads

Loads are interrupted and discontinued for a number of reasons. A primary reason is space errors, in which SQL*Loader runs out of space for data rows or index entries. A load might also be discontinued because the maximum number of errors was exceeded, an unexpected error was returned to SQL*Loader from the server, a record was too long in the datafile, or a Control+C was executed.

The behavior of SQL*Loader when a load is discontinued varies depending on whether it is a conventional path load or a direct path load, and on the reason the load was interrupted. Additionally, when an interrupted load is continued, the use and value of the SKIP parameter can vary depending on the particular case. The following sections explain the possible scenarios.

See Also:

SKIP (records to skip) on page 4-13

Discontinued Conventional Path Loads

In a conventional path load, data is committed after all data in the bind array is loaded into all tables. If the load is discontinued, only the rows that were processed up to the time of the last commit operation are loaded. There is no partial commit of data.

Discontinued Direct Path Loads

In a direct path load, the behavior of a discontinued load varies depending on the reason the load was discontinued.

■

■

Load Discontinued Because of Space Errors

If there is one INTO TABLE statement in the control file and a space error occurs, the following scenarios can take place:

If you are loading data into an unpartitioned table, one partition of a partitioned table, or one subpartition of a composite partitioned table, then

SQL*Loader commits as many rows as were loaded before the error occurred.

This is independent of whether the ROWS parameter was specified.

If you are loading data into multiple subpartitions (that is, loading into a partitioned table, a composite partitioned table, or one partition of a composite

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Interrupted Loads

■ partitioned table), the load is discontinued and no data is saved unless ROWS has been specified. In that case, all data that was previously committed will be saved.

If there are multiple INTO TABLE statements in the control file and a space error occurs on one of those tables, the following scenarios can take place:

■

If the space error occurs when you are loading data into an unpartitioned table, one partition of a partitioned table, or one subpartition of a composite partitioned table, SQL*Loader attempts to load data already read from the datafile into other tables. SQL*Loader then commits as many rows as were loaded before the error occurred. This is independent of whether the ROWS parameter was specified. In this scenario, a different number of rows could be loaded into each table; to continue the load you would need to specify a different value for the SKIP parameter for every table. SQL*Loader only reports the value for the SKIP parameter if it is the same for all tables.

If the space error occurs when you are loading data into multiple subpartitions

(that is, loading into a partitioned table, a composite partitioned table, or one partition of a composite partitioned table), the load is discontinued for all tables and no data is saved unless ROWS has been specified. In that case, all data that was previously committed is saved, and when you continue the load the value you supply for the SKIP parameter will be the same for all tables.

Load Discontinued Because Maximum Number of Errors Exceeded

If the maximum number of errors is exceeded, SQL*Loader stops loading records into any table and the work done to that point is committed. This means that when you continue the load, the value you specify for the SKIP parameter may be different for different tables. SQL*Loader only reports the value for the SKIP parameter if it is the same for all tables.

Load Discontinued Because of Fatal Errors

If a fatal error is encountered, the load is stopped and no data is saved unless ROWS was specified at the beginning of the load. In that case, all data that was previously committed is saved. SQL*Loader only reports the value for the SKIP parameter if it is the same for all tables.

Load Discontinued Because a Control+C Was Issued

If SQL*Loader is in the middle of saving data when a Control+C is issued, it continues to do the save and then stops the load after the save completes.

Otherwise, SQL*Loader stops the load without committing any work that was not

SQL*Loader Control File Reference

5-25

Interrupted Loads committed already. This means that the value of the SKIP parameter will be the same for all tables.

Status of Tables and Indexes After an Interrupted Load

When a load is discontinued, any data already loaded remains in the tables, and the tables are left in a valid state. If the conventional path is used, all indexes are left in a valid state.

If the direct path load method is used, any indexes that run out of space are left in an unusable state. You must drop these indexes before the load can continue. You can re-create the indexes either before continuing or after the load completes.

Other indexes are valid if no other errors occurred. See Indexes Left in an Unusable

State on page 9-12 for other reasons why an index might be left in an unusable state.

Using the Log File to Determine Load Status

The SQL*Loader log file tells you the state of the tables and indexes and the number of logical records already read from the input datafile. Use this information to resume the load where it left off.

Continuing Single-Table Loads

When SQL*Loader must discontinue a direct path or conventional path load before it is finished, some rows have probably already been committed or marked with savepoints. To continue the discontinued load, use the SKIP parameter to specify the number of logical records that have already been processed by the previous load. At the time the load is discontinued, the value for SKIP is written to the log file in a message similar to the following:

Specify SKIP=1001 when continuing the load.

This message specifying the value of the SKIP parameter is preceded by a message indicating why the load was discontinued.

Note that for multiple-table loads, the value of the SKIP parameter is displayed only if it is the same for all tables.

See Also:

SKIP (records to skip) on page 4-13

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Assembling Logical Records from Physical Records

Assembling Logical Records from Physical Records

Because Oracle9i supports user-defined record sizes larger than 64 KB (see

READSIZE (read buffer size) on page 4-10), the need to break up logical records into multiple physical records is reduced. However, there may still be situations in which you may want to do so. At some point, when you want to combine those multiple physical records back into one logical record, you can use one of the following clauses, depending on your data:

■

CONCATENATE

■

CONTINUEIF

Using CONCATENATE to Assemble Logical Records

Use CONCATENATE when you want SQL*Loader to always combine the same number of physical records to form one logical record. In the following example, integer

specifies the number of physical records to combine.

CONCATENATE integer

The integer value specified for CONCATENATE determines the number of physical record structures that SQL*Loader allocates for each row in the column array.

Because the default value for COLUMNARRAYROWS is large, if you also specify a large value for CONCATENATE, then excessive memory allocation can occur. If this happens, you can improve performance by reducing the value of the

COLUMNARRAYROWS

parameter to lower the number of rows in a column array.

See Also:

■

■

COLUMNARRAYROWS on page 4-4

Specifying the Number of Column Array Rows and Size of

Stream Buffers on page 9-21

Using CONTINUEIF to Assemble Logical Records

Use CONTINUEIF if the number of physical records to be continued varies. The parameter CONTINUEIF is followed by a condition that is evaluated for each physical record, as it is read. For example, two records might be combined if a pound sign (#) were in byte position 80 of the first record. If any other character were there, the second record would not be added to the first.

The full syntax for CONTINUEIF adds even more flexibility:

SQL*Loader Control File Reference

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Assembling Logical Records from Physical Records

CONTINUEIF

LAST

THIS

NEXT

PRESERVE

PRESERVE

(

( pos_spec operator str

X’hex_str’

)

Table 5–2 describes the parameters for CONTINUEIF.

Table 5–2 Parameters for CONTINUEIF

Parameter

THIS

NEXT operator

LAST

Description

If the condition is true in the current record, then the next physical record is read and concatenated to the current physical record, continuing until the condition is false. If the condition is false, then the current physical record becomes the last physical record of the current logical record. THIS is the default.

If the condition is true in the next record, then the current physical record is concatenated to the current logical record, continuing until the condition is false.

The supported operators are equal and not equal.

For the equal operator, the field and comparison string must match exactly for the condition to be true. For the not equal operator, they may differ in any character.

This test is similar to THIS, but the test is always against the last nonblank character. If the last nonblank character in the current physical record meets the test, then the next physical record is read and concatenated to the current physical record, continuing until the condition is false. If the condition is false in the current record, then the current physical record is the last physical record of the current logical record.

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Table 5–2 (Cont.) Parameters for CONTINUEIF

Parameter

pos_spec str

X’hex-str’

PRESERVE

Description

Specifies the starting and ending column numbers in the physical record.

Column numbers start with 1. Either a hyphen or a colon is acceptable (start-end or start:end).

If you omit end, the length of the continuation field is the length of the byte string or character string. If you use end, and the length of the resulting continuation field is not the same as that of the byte string or the character string, the shorter one is padded. Character strings are padded with blanks, hexadecimal strings with zeros.

A string of characters to be compared to the continuation field defined by start and end, according to the operator. The string must be enclosed in double or single quotation marks. The comparison is made character by character, blank padding on the right if necessary.

A string of bytes in hexadecimal format used in the same way as str. X’1FB033 would represent the three bytes with values 1F,

B0, and 33 (hexadecimal).

Includes ’char_string’ or X’hex_string’ in the logical record. The default is to exclude them.

Note:

The positions in the CONTINUEIF clause refer to positions in each physical record. This is the only time you refer to positions in physical records. All other references are to logical records.

If the PRESERVE parameter is not used, the continuation field is removed from all physical records when the logical record is assembled. That is, data values are allowed to span the records with no extra characters (continuation characters) in the middle.

If the PRESERVE parameter is used, the continuation field is kept in all physical records when the logical record is assembled.

Example 5–2 through Example 5–5 show the use of CONTINUEIF THIS and

CONTINUEIF NEXT,

with and without the PRESERVE parameter.

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5-29

Assembling Logical Records from Physical Records

Example 5–2 CONTINUEIF THIS Without the PRESERVE Parameter

Assume that you have physical records 14 bytes long and that a period represents a space:

%%aaaaaaaa....

%%bbbbbbbb....

..cccccccc....

%%dddddddddd..

%%eeeeeeeeee..

..ffffffffff..

In this example, the CONTINUEIF THIS clause does not use the PRESERVE parameter:

CONTINUEIF THIS (1:2) = ’%%’

Therefore, the logical records are assembled as follows:

aaaaaaaa....bbbbbbbb....cccccccc....

dddddddddd..eeeeeeeeee..ffffffffff..

Note that columns 1 and 2 (for example, %% in physical record 1) are removed from the physical records when the logical records are assembled.

Example 5–3 CONTINUEIF THIS with the PRESERVE Parameter

Assume that you have the same physical records as in Example 5–2 .

In this example, the CONTINUEIF THIS clause uses the PRESERVE parameter:

CONTINUEIF THIS PRESERVE (1:2) = ’%%’

Therefore, the logical records are assembled as follows:

%%aaaaaaaa....%%bbbbbbbb......cccccccc....

%%dddddddddd..%%eeeeeeeeee....ffffffffff..

Note that columns 1 and 2 are not removed from the physical records when the logical records are assembled.

Example 5–4 CONTINUEIF NEXT Without the PRESERVE Parameter

Assume that you have physical records 14 bytes long and that a period represents a space:

..aaaaaaaa....

%%bbbbbbbb....

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%%cccccccc....

..dddddddddd..

%%eeeeeeeeee..

%%ffffffffff..

In this example, the CONTINUEIF NEXT clause does not use the PRESERVE parameter:

CONTINUEIF NEXT (1:2) = ’%%’

Therefore, the logical records are assembled as follows (the same results as for

Example 5–2 ).

aaaaaaaa....bbbbbbbb....cccccccc....

dddddddddd..eeeeeeeeee..ffffffffff..

Example 5–5 CONTINUEIF NEXT with the PRESERVE Parameter

Assume that you have the same physical records as in Example 5–4 .

In this example, the CONTINUEIF NEXT clause uses the PRESERVE parameter:

CONTINUEIF NEXT PRESERVE (1:2) = ’%%’

Therefore, the logical records are assembled as follows:

..aaaaaaaa....%%bbbbbbbb....%%cccccccc....

..dddddddddd..%%eeeeeeeeee..%%ffffffffff..

See Also:

Case Study 4: Loading Combined Physical Records on page 10-14 for an example of the CONTINUEIF clause

Loading Logical Records into Tables

This section describes the way in which you specify:

■

■

■

■

Which tables you want to load

Which records you want to load into them

Default data delimiters for those records

How to handle short records with missing data

SQL*Loader Control File Reference

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Loading Logical Records into Tables

Specifying Table Names

The INTO TABLE clause of the LOAD DATA statement allows you to identify tables, fields, and datatypes. It defines the relationship between records in the datafile and tables in the database. The specification of fields and datatypes is described in later sections.

INTO TABLE Clause

Among its many functions, the INTO TABLE clause allows you to specify the table into which you load data. To load multiple tables, you include one INTO TABLE clause for each table you wish to load.

To begin an INTO TABLE clause, use the keywords INTO TABLE, followed by the name of the Oracle table that is to receive the data.

The syntax is as follows:

INTO TABLE name

(

PARTITION

SUBPARTITION name name

)

INSERT

REPLACE

TRUNCATE

APPEND

The table must already exist. The table name should be enclosed in double quotation marks if it is the same as any SQL or SQL*Loader reserved keyword, if it contains any special characters, or if it is case sensitive.

INTO TABLE scott."CONSTANT"

INTO TABLE scott."Constant"

INTO TABLE scott."-CONSTANT"

The user must have INSERT privileges for the table being loaded. If the table is not in the user’s schema, then the user must either use a synonym to reference the table or include the schema name as part of the table name (for example, scott.emp).

Table-Specific Loading Method

When you are loading a table, you can use the INTO TABLE clause to specify a table-specific loading method (INSERT, APPEND, REPLACE, or TRUNCATE) that applies only to that table. That method overrides the global table-loading method.

The global table-loading method is INSERT, by default, unless a different method

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Loading Logical Records into Tables was specified before any INTO TABLE clauses. The following sections discuss using these options to load data into empty and nonempty tables.

Loading Data into Empty Tables

If the tables you are loading into are empty, use the INSERT option.

INSERT

This is SQL*Loader’s default method. It requires the table to be empty before loading. SQL*Loader terminates with an error if the table contains rows.

Case Study 1: Loading Variable-Length Data on page 10-5 provides an example.

■

■

■

Loading Data into Nonempty Tables

If the tables you are loading into already contain data, you have three options:

APPEND

REPLACE

TRUNCATE

Caution:

When REPLACE or TRUNCATE is specified, the entire

table is replaced, not just individual rows. After the rows are successfully deleted, a commit is issued. You cannot recover the data that was in the table before the load, unless it was saved with

Export or a comparable utility.

Note:

This section corresponds to the DB2 keyword RESUME; users of DB2 should also refer to the description of RESUME in

Appendix B .

APPEND

If data already exists in the table, SQL*Loader appends the new rows to it.

If data does not already exist, the new rows are simply loaded. You must have

SELECT

privilege to use the APPEND option.

Case Study 3: Loading a Delimited,

Free-Format File on page 10-11 provides an example.

REPLACE

With REPLACE, all rows in the table are deleted and the new data is loaded. The table must be in your schema, or you must have DELETE privilege on the table.

Case Study 4: Loading Combined Physical Records on page 10-14 provides an example.

SQL*Loader Control File Reference

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Loading Logical Records into Tables

The row deletes cause any delete triggers defined on the table to fire. If DELETE

CASCADE

has been specified for the table, then the cascaded deletes are carried out.

For more information on cascaded deletes, see the information about data integrity in Oracle9i Database Concepts.

Updating Existing Rows

The REPLACE method is a table replacement, not a replacement of individual rows. SQL*Loader does not update existing records, even if they have null columns. To update existing rows, use the following procedure:

1.

2.

Load your data into a work table.

Use the SQL language UPDATE statement with correlated subqueries.

3.

Drop the work table.

For more information, see the UPDATE statement in Oracle9i SQL Reference.

TRUNCATE

The SQL TRUNCATE statement quickly and efficiently deletes all rows from a table or cluster, to achieve the best possible performance. For the TRUNCATE statement to operate, the table’s referential integrity constraints must first be disabled. If they have not been disabled, SQL*Loader returns an error.

Once the integrity constraints have been disabled, DELETE CASCADE is no longer defined for the table. If the DELETE CASCADE functionality is needed, then the contents of the table must be manually deleted before the load begins.

The table must be in your schema, or you must have the DROP ANY TABLE privilege.

See Also:

Oracle9i Database Administrator’s Guide for more information about the TRUNCATE statement

Table-Specific OPTIONS Parameter

The OPTIONS parameter can be specified for individual tables in a parallel load. (It is only valid for a parallel load.)

The syntax for the OPTIONS parameter is as follows:

OPTIONS ( FILE=database_filename )

See Also:

Parameters for Parallel Direct Path Loads on page 9-33

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Loading Logical Records into Tables

Loading Records Based on a Condition

You can choose to load or discard a logical record by using the WHEN clause to test a condition in the record.

The WHEN clause appears after the table name and is followed by one or more field conditions. The syntax for field_condition is as follows:

AND

( full_fieldname pos_spec operator

’char_string’

X’hex_string’

BLANKS

)

For example, the following clause indicates that any record with the value "q" in the fifth column position should be loaded:

WHEN (5) = ’q’

A WHEN clause can contain several comparisons, provided each is preceded by AND.

Parentheses are optional, but should be used for clarity with multiple comparisons joined by AND, for example:

WHEN (deptno = ’10’) AND (job = ’SALES’)

See Also:

■

■

Using the WHEN, NULLIF, and DEFAULTIF Clauses on page 6-32 for information about how SQL*Loader evaluates

WHEN

clauses, as opposed to NULLIF and DEFAULTIF clauses

Case Study 5: Loading Data into Multiple Tables on page 10-18 provides an example of the WHEN clause

Using the WHEN Clause with LOBFILEs and SDFs

If a record with a LOBFILE or SDF is discarded, SQL*Loader skips the corresponding data in that LOBFILE or SDF.

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Loading Logical Records into Tables

Specifying Default Data Delimiters

If all data fields are terminated similarly in the datafile, you can use the FIELDS clause to indicate the default delimiters. The syntax for the fields_spec, termination_spec,

and enclosure_spec clauses is as follows:

fields_spec

enclosure_spec

OPTIONALLY

FIELDS enclosure_spec termination_spec

termination_spec

TERMINATED

BY

WHITESPACE

X’hexstr’

’string’

EOF

Note:

Terminator strings can contain one or more characters. Also,

TERMINATED BY EOF

applies only to loading LOBs from

LOBFILE.

enclosure_spec

BY

’string’

X’hexstr’

AND

’string’

X’hexstr’

ENCLOSED

Note:

Enclosure strings can contain one or more characters.

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Loading Logical Records into Tables

You can override the delimiter for any given column by specifying it after the column name.

Case Study 3: Loading a Delimited, Free-Format File on page 10-11 provides an example.

See Also:

■

■

Specifying Delimiters on page 6-24 for a complete description of the syntax

Loading LOB Data from LOBFILEs on page 7-23

Handling Short Records with Missing Data

When the control file definition specifies more fields for a record than are present in the record, SQL*Loader must determine whether the remaining (specified) columns should be considered null or whether an error should be generated.

If the control file definition explicitly states that a field’s starting position is beyond the end of the logical record, then SQL*Loader always defines the field as null. If a field is defined with a relative position (such as dname and loc in the following example), and the record ends before the field is found, then SQL*Loader could either treat the field as null or generate an error. SQL*Loader uses the presence or absence of the TRAILING NULLCOLS clause (shown in the following syntax diagram) to determine the course of action.

OID_spec

SID_spec FIELDS delim_spec

TRAILING

NULLCOLS

TREAT AS typename

TRAILING NULLCOLS Clause

The TRAILING NULLCOLS clause tells SQL*Loader to treat any relatively positioned columns that are not present in the record as null columns.

For example, consider the following data:

10 Accounting

Assume that the preceding data is read with the following control file and the record ends after dname:

SQL*Loader Control File Reference

5-37

Index Options

INTO TABLE dept

TRAILING NULLCOLS

( deptno CHAR TERMINATED BY " ",

dname CHAR TERMINATED BY WHITESPACE,

loc CHAR TERMINATED BY WHITESPACE

)

In this case, the remaining loc field is set to null. Without the TRAILING

NULLCOLS

clause, an error would be generated due to missing data.

See Also:

Case Study 7: Extracting Data from a Formatted Report on page 10-28 for an example of TRAILING NULLCOLS

Index Options

This section describes the following SQL*Loader options that control how index entries are created:

■

SORTED INDEXES

■

SINGLEROW

SORTED INDEXES Clause

The SORTED INDEXES clause applies to direct path loads. It tells SQL*Loader that the incoming data has already been sorted on the specified indexes, allowing

SQL*Loader to optimize performance.

See Also:

SORTED INDEXES Clause on page 9-18

SINGLEROW Option

The SINGLEROW option is intended for use during a direct path load with APPEND on systems with limited memory, or when loading a small number of records into a large table. This option inserts each index entry directly into the index, one record at a time.

By default, SQL*Loader does not use SINGLEROW to append records to a table.

Instead, index entries are put into a separate, temporary storage area and merged with the original index at the end of the load. This method achieves better performance and produces an optimal index, but it requires extra storage space.

During the merge, the original index, the new index, and the space for new entries all simultaneously occupy storage space.

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Benefits of Using Multiple INTO TABLE Clauses

With the SINGLEROW option, storage space is not required for new index entries or for a new index. The resulting index may not be as optimal as a freshly sorted one, but it takes less space to produce. It also takes more time because additional UNDO information is generated for each index insert. This option is suggested for use when either of the following situations exists:

■

Available storage is limited.

■

The number of records to be loaded is small compared to the size of the table (a ratio of 1:20 or less is recommended).

Benefits of Using Multiple INTO TABLE Clauses

Multiple INTO TABLE clauses allow you to:

■

■

■

■

Load data into different tables

Extract multiple logical records from a single input record

Distinguish different input record formats

Distinguish different input row object subtypes

In the first case, it is common for the INTO TABLE clauses to refer to the same table.

This section illustrates the different ways to use multiple INTO TABLE clauses and shows you how to use the POSITION parameter.

Note:

A key point when using multiple INTO TABLE clauses is that field scanning continues from where it left off when a new INTO

TABLE

clause is processed. The remainder of this section details important ways to make use of that behavior. It also describes alternative ways using fixed field locations or the POSITION parameter.

Extracting Multiple Logical Records

Some data storage and transfer media have fixed-length physical records. When the data records are short, more than one can be stored in a single, physical record to use the storage space efficiently.

In this example, SQL*Loader treats a single physical record in the input file as two logical records and uses two INTO TABLE clauses to load the data into the emp table. For example, assume the data is as follows:

1119 Smith 1120 Yvonne

SQL*Loader Control File Reference

5-39

Benefits of Using Multiple INTO TABLE Clauses

1121 Albert 1130 Thomas

The following control file extracts the logical records:

INTO TABLE emp

(empno POSITION(1:4) INTEGER EXTERNAL,

ename POSITION(6:15) CHAR)

INTO TABLE emp

(empno POSITION(17:20) INTEGER EXTERNAL,

ename POSITION(21:30) CHAR)

Relative Positioning Based on Delimiters

The same record could be loaded with a different specification. The following control file uses relative positioning instead of fixed positioning. It specifies that each field is delimited by a single blank (" ") or with an undetermined number of blanks and tabs (WHITESPACE):

INTO TABLE emp

(empno INTEGER EXTERNAL TERMINATED BY " ",

ename CHAR TERMINATED BY WHITESPACE)

INTO TABLE emp

(empno INTEGER EXTERNAL TERMINATED BY " ",

ename CHAR) TERMINATED BY WHITESPACE)

The important point in this example is that the second empno field is found immediately after the first ename, although it is in a separate INTO TABLE clause.

Field scanning does not start over from the beginning of the record for a new INTO

TABLE

clause. Instead, scanning continues where it left off.

To force record scanning to start in a specific location, you use the POSITION parameter. That mechanism is described in Distinguishing Different Input Record

Formats on page 5-40 and in Loading Data into Multiple Tables on page 5-43.

Distinguishing Different Input Record Formats

A single datafile might contain records in a variety of formats. Consider the following data, in which emp and dept records are intermixed:

1 50 Manufacturing — DEPT record

2 1119 Smith 50 — EMP record

2 1120 Snyder 50

1 60 Shipping

2 1121 Stevens 60

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Benefits of Using Multiple INTO TABLE Clauses

A record ID field distinguishes between the two formats. Department records have a 1 in the first column, while employee records have a 2. The following control file uses exact positioning to load this data:

INTO TABLE dept

WHEN recid = 1

(recid FILLER POSITION(1:1) INTEGER EXTERNAL,

deptno POSITION(3:4) INTEGER EXTERNAL,

dname POSITION(8:21) CHAR)

INTO TABLE emp

WHEN recid <> 1

(recid FILLER POSITION(1:1) INTEGER EXTERNAL,

empno POSITION(3:6) INTEGER EXTERNAL,

ename POSITION(8:17) CHAR,

deptno POSITION(19:20) INTEGER EXTERNAL)

Relative Positioning Based on the POSITION Parameter

The records in the previous example could also be loaded as delimited data. In this case, however, it is necessary to use the POSITION parameter. The following control file could be used:

INTO TABLE dept

WHEN recid = 1

(recid FILLER INTEGER EXTERNAL TERMINATED BY WHITESPACE,

deptno INTEGER EXTERNAL TERMINATED BY WHITESPACE,

dname CHAR TERMINATED BY WHITESPACE)

INTO TABLE emp

WHEN recid <> 1

(recid FILLER POSITION(1) INTEGER EXTERNAL TERMINATED BY ’ ’,

empno INTEGER EXTERNAL TERMINATED BY ’ ’

ename CHAR TERMINATED BY WHITESPACE,

deptno INTEGER EXTERNAL TERMINATED BY ’ ’)

The POSITION parameter in the second INTO TABLE clause is necessary to load this data correctly. It causes field scanning to start over at column 1 when checking for data that matches the second format. Without it, SQL*Loader would look for the recid

field after dname.

Distinguishing Different Input Row Object Subtypes

A single datafile may contain records made up of row objects inherited from the same base row object type. For example, consider the following simple object type

SQL*Loader Control File Reference

5-41

Benefits of Using Multiple INTO TABLE Clauses and object table definitions in which a nonfinal base object type is defined along with two object subtypes that inherit from the base type:

CREATE TYPE person_t AS OBJECT

(name VARCHAR2(30),

age NUMBER(3)) not final;

CREATE TYPE employee_t UNDER person_t

(empid NUMBER(5),

deptno NUMBER(4),

dept VARCHAR2(30)) not final;

CREATE TYPE student_t UNDER person_t

(stdid NUMBER(5),

major VARCHAR2(20)) not final;

CREATE TABLE persons OF person_t;

The following input datafile contains a mixture of these row objects subtypes. A type ID field distinguishes between the three subtypes. person_t objects have a P in the first column, employee_t objects have an E, and student_t objects have an S.

P,James,31,

P,Thomas,22,

E,Pat,38,93645,1122,Engineering,

P,Bill,19,

P,Scott,55,

S,Judy,45,27316,English,

S,Karen,34,80356,History,

E,Karen,61,90056,1323,Manufacturing,

S,Pat,29,98625,Spanish,

S,Cody,22,99743,Math,

P,Ted,43,

E,Judy,44,87616,1544,Accounting,

E,Bob,50,63421,1314,Shipping,

S,Bob,32,67420,Psychology,

E,Cody,33,25143,1002,Human Resources,

The following control file uses relative positioning based on the POSITION parameter to load this data. Note the use of the TREAT AS clause with a specific object type name. This informs SQL*Loader that all input row objects for the object table will conform to the definition of the named object type.

INTO TABLE persons

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REPLACE

WHEN typid = ’P’ TREAT AS person_t

FIELDS TERMINATED BY ","

(typid FILLER POSITION(1) CHAR,

name CHAR,

age CHAR)

INTO TABLE persons

REPLACE

WHEN typid = ’E’ TREAT AS employee_t

FIELDS TERMINATED BY ","

(typid FILLER POSITION(1) CHAR,

name CHAR,

age CHAR,

empid CHAR,

deptno CHAR,

dept CHAR)

INTO TABLE persons

REPLACE

WHEN typid = ’S’ TREAT AS student_t

FIELDS TERMINATED BY ","

(typid FILLER POSITION(1) CHAR,

name CHAR,

age CHAR,

stdid CHAR,

major CHAR)

See Also:

Loading Column Objects on page 7-1 for more information on loading object types

Loading Data into Multiple Tables

By using the POSITION clause with multiple INTO TABLE clauses, data from a single record can be loaded into multiple normalized tables. See Case Study 5:

Loading Data into Multiple Tables on page 10-18.

Summary

Multiple INTO TABLE clauses allow you to extract multiple logical records from a single input record and recognize different record formats in the same file.

For delimited data, proper use of the POSITION parameter is essential for achieving the expected results.

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Bind Arrays and Conventional Path Loads

When the POSITION parameter is not used, multiple INTO TABLE clauses process different parts of the same (delimited data) input record, allowing multiple tables to be loaded from one record. When the POSITION parameter is used, multiple INTO

TABLE

clauses can process the same record in different ways, allowing multiple formats to be recognized in one input file.

Bind Arrays and Conventional Path Loads

SQL*Loader uses the SQL array-interface option to transfer data to the database.

Multiple rows are read at one time and stored in the bind array. When SQL*Loader sends the Oracle database an INSERT command, the entire array is inserted at one time. After the rows in the bind array are inserted, a COMMIT is issued.

The determination of bind array size pertains to SQL*Loader’s conventional path option. It does not apply to the direct path load method because a direct path load uses the direct path API, rather than Oracle’s SQL interface.

See Also:

Oracle Call Interface Programmer’s Guide for more information about the concepts of direct path loading

Size Requirements for Bind Arrays

The bind array must be large enough to contain a single row. If the maximum row length exceeds the size of the bind array, as specified by the BINDSIZE parameter,

SQL*Loader generates an error. Otherwise, the bind array contains as many rows as can fit within it, up to the limit set by the value of the ROWS parameter.

The BINDSIZE and ROWS parameters are described in Command-Line Parameters on page 4-3.

Although the entire bind array need not be in contiguous memory, the buffer for each field in the bind array must occupy contiguous memory. If the operating system cannot supply enough contiguous memory to store a field, SQL*Loader generates an error.

Performance Implications of Bind Arrays

Large bind arrays minimize the number of calls to the Oracle database server and maximize performance. In general, you gain large improvements in performance with each increase in the bind array size up to 100 rows. Increasing the bind array size to be greater than 100 rows generally delivers more modest improvements in performance. The size (in bytes) of 100 rows is typically a good value to use.

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Bind Arrays and Conventional Path Loads

In general, any reasonably large size permits SQL*Loader to operate effectively. It is not usually necessary to perform the detailed calculations described in this section.

Read this section when you need maximum performance or an explanation of memory usage.

Specifying Number of Rows Versus Size of Bind Array

When you specify a bind array size using the command-line parameter BINDSIZE

(see BINDSIZE (maximum size) on page 4-4) or the OPTIONS clause in the control file (see OPTIONS Clause on page 5-4), you impose an upper limit on the bind array. The bind array never exceeds that maximum.

As part of its initialization, SQL*Loader determines the size in bytes required to load a single row. If that size is too large to fit within the specified maximum, the load terminates with an error.

SQL*Loader then multiplies that size by the number of rows for the load, whether that value was specified with the command-line parameter ROWS (see ROWS (rows per commit) on page 4-12) or the OPTIONS clause in the control file (see OPTIONS

Clause on page 5-4).

If that size fits within the bind array maximum, the load continues—SQL*Loader does not try to expand the number of rows to reach the maximum bind array size. If

the number of rows and the maximum bind array size are both specified, SQL*Loader always uses the smaller value for the bind array.

If the maximum bind array size is too small to accommodate the initial number of rows, SQL*Loader uses a smaller number of rows that fits within the maximum.

Calculations to Determine Bind Array Size

The bind array’s size is equivalent to the number of rows it contains times the maximum length of each row. The maximum length of a row is equal to the sum of the maximum field lengths, plus overhead, as follows: bind array size =

(number of rows) * ( SUM(fixed field lengths)

+ SUM(maximum varying field lengths)

+ ( (number of varying length fields)

* (size of length indicator) )

)

Many fields do not vary in size. These fixed-length fields are the same for each loaded row. For these fields, the maximum length of the field is the field size, in

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5-45

Bind Arrays and Conventional Path Loads bytes, as described in SQL*Loader Datatypes on page 6-7. There is no overhead for these fields.

The fields that can vary in size from row to row are:

■

CHAR

■

DATE

■

INTERVAL DAY TO SECOND

■

INTERVAL DAY TO YEAR

■

■

■

■

LONG VARRAW numeric EXTERNAL

TIME

TIMESTAMP

■

TIME WITH TIME ZONE

TIMESTAMP WITH TIME ZONE

■

■

VARCHAR

VARCHARC

■

■

VARGRAPHIC

VARRAW

■

■

VARRAWC

The maximum length of these datatypes is described in SQL*Loader Datatypes on page 6-7. The maximum lengths describe the number of bytes that the fields can occupy in the input data record. That length also describes the amount of storage that each field occupies in the bind array, but the bind array includes additional overhead for fields that can vary in size.

When the character datatypes (CHAR, DATE, and numeric EXTERNAL) are specified with delimiters, any lengths specified for these fields are maximum lengths. When specified without delimiters, the size in the record is fixed, but the size of the inserted field may still vary, due to whitespace trimming. So internally, these datatypes are always treated as varying-length fields—even when they are fixed-length fields.

A length indicator is included for each of these fields in the bind array. The space reserved for the field in the bind array is large enough to hold the longest possible

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Bind Arrays and Conventional Path Loads value of the field. The length indicator gives the actual length of the field for each row.

Note:

In conventional path loads, LOBFILEs are not included when allocating the size of a bind array.

Determining the Size of the Length Indicator

On most systems, the size of the length indicator is 2 bytes. On a few systems, it is 3 bytes. To determine its size, use the following control file:

OPTIONS (ROWS=1)

LOAD DATA

INFILE *

APPEND

INTO TABLE DEPT

(deptno POSITION(1:1) CHAR(1))

BEGINDATA a

This control file loads a 1-byte CHAR using a 1-row bind array. In this example, no data is actually loaded because a conversion error occurs when the character a is loaded into a numeric column (deptno). The bind array size shown in the log file, minus one (the length of the character field) is the value of the length indicator.

Note:

A similar technique can determine bind array size without doing any calculations. Run your control file without any data and with ROWS=1 to determine the memory requirements for a single row of data. Multiply by the number of rows you want in the bind array to determine the bind array size.

Calculating the Size of Field Buffers

Table 5–3 through Table 5–6 summarize the memory requirements for each datatype. "L" is the length specified in the control file. "P" is precision. "S" is the size of the length indicator. For more information on these values, see SQL*Loader

Datatypes on page 6-7.

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Bind Arrays and Conventional Path Loads

.

Table 5–3 Fixed-Length Fields

Datatype

INTEGER

INTEGER(

SMALLINT

FLOAT

DOUBLE

BYTEINT

VARRAW

N )

LONG VARRAW

VARCHARC

VARRAWC

Size in Bytes (Operating System-Dependent)

The size of the INT datatype, in C

N

bytes

The size of SHORT INT datatype, in C

The size of the FLOAT datatype, in C

The size of the DOUBLE datatype, in C

The size of UNSIGNED CHAR, in C

The size of UNSIGNED SHORT, plus 4096 bytes or whatever is specified as max_length

The size of UNSIGNED INT, plus 4096 bytes or whatever is specified as max_length

Composed of 2 numbers. The first specifies length, and the second (which is optional) specifies

4096 bytes).

max_length

(default is

This datatype is for RAW data. It is composed of 2 numbers.

The first specifies length, and the second (which is optional) specifies max_length

(default is 4096 bytes).

Table 5–4 Nongraphic Fields

Datatype

(packed) DECIMAL

ZONED

RAW

CHAR

(no delimiters) datetime and interval (no delimiters) numeric EXTERNAL (no delimiters)

Default Size Specified Size

None

None

(N+1)/2, rounded up

P

None

1

None

None

L

L+S

L+S

L+S

Table 5–5 Graphic Fields

Datatype

GRAPHIC

Default Size

None

Length Specified with POSITION

L

Length Specified with DATATYPE

2*L

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Bind Arrays and Conventional Path Loads

Table 5–5 (Cont.) Graphic Fields

Datatype

GRAPHIC

EXTERNAL

VARGRAPHIC

Default Size

None

4Kb*2

Length Specified with POSITION

L - 2

L+S

Length Specified with DATATYPE

2*(L-2)

(2*L)+S

Table 5–6 Variable-Length Fields

Datatype Default Size

VARCHAR

CHAR

(delimited)

4Kb

255 datetime and interval (delimited) 255 numeric EXTERNAL (delimited) 255

Maximum Length

Specified (L)

L+S

L+S

L+S

L+S

Minimizing Memory Requirements for Bind Arrays

Pay particular attention to the default sizes allocated for VARCHAR, VARGRAPHIC, and the delimited forms of CHAR, DATE, and numeric EXTERNAL fields. They can consume enormous amounts of memory—especially when multiplied by the number of rows in the bind array. It is best to specify the smallest possible maximum length for these fields. Consider the following example:

CHAR(10) TERMINATED BY ","

With byte-length semantics, this example uses (10 + 2) * 64 = 768 bytes in the bind array, assuming that the length indicator is 2 bytes long and that 64 rows are loaded at a time.

With character-length semantics, the same example uses ((10 * s) + 2) * 64 bytes in the bind array, where "s" is the maximum size in bytes of a character in the datafile character set.

Now consider the following example:

CHAR TERMINATED BY ","

Regardless of whether byte-length semantics or character-length semantics are used, this example uses (255 + 2) * 64 = 16,448 bytes, because the default maximum

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5-49

Bind Arrays and Conventional Path Loads size for a delimited field is 255 bytes. This can make a considerable difference in the number of rows that fit into the bind array.

Calculating Bind Array Size for Multiple INTO TABLE Clauses

When calculating a bind array size for a control file that has multiple INTO TABLE clauses, calculate as if the INTO TABLE clauses were not present. Imagine all of the fields listed in the control file as one, long data structure—that is, the format of a single row in the bind array.

If the same field in the data record is mentioned in multiple INTO TABLE clauses, additional space in the bind array is required each time it is mentioned. It is especially important to minimize the buffer allocations for such fields.

Note:

Generated data is produced by the SQL*Loader functions

CONSTANT

, EXPRESSION, RECNUM, SYSDATE, and SEQUENCE. Such generated data does not require any space in the bind array.

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6

Field List Reference

This chapter describes the field-list portion of the SQL*Loader control file. The following topics are included:

■

■

Field List Contents

Specifying the Position of a Data Field

■

■

■

■

Specifying Columns and Fields

SQL*Loader Datatypes

Specifying Field Conditions

Using the WHEN, NULLIF, and DEFAULTIF Clauses

■

■

■

■

■

■

■

Loading Data Across Different Platforms

Byte Ordering

Loading All-Blank Fields

Trimming Whitespace

Preserving Whitespace

Applying SQL Operators to Fields

Using SQL*Loader to Generate Data for Input

Field List Contents

The field-list portion of a SQL*Loader control file provides information about fields being loaded, such as position, datatype, conditions, and delimiters.

Example 6–1 shows the field list section of the sample control file that was introduced in Chapter 5.

Field List Reference

6-1

Field List Contents

Example 6–1 Field List Section of Sample Control File

.

.

.

1

(hiredate SYSDATE,

2

deptno POSITION(1:2) INTEGER EXTERNAL(2)

NULLIF deptno=BLANKS,

3

job POSITION(7:14) CHAR TERMINATED BY WHITESPACE

NULLIF job=BLANKS "UPPER(:job)",

mgr POSITION(28:31) INTEGER EXTERNAL

TERMINATED BY WHITESPACE, NULLIF mgr=BLANKS,

ename POSITION(34:41) CHAR

TERMINATED BY WHITESPACE "UPPER(:ename)",

empno POSITION(45) INTEGER EXTERNAL

TERMINATED BY WHITESPACE,

sal POSITION(51) CHAR TERMINATED BY WHITESPACE

"TO_NUMBER(:sal,’$99,999.99’)",

4

comm INTEGER EXTERNAL ENCLOSED BY ’(’ AND ’%’

":comm * 100"

)

In this sample control file, the numbers that appear to the left would not appear in a real control file. They are keyed in this sample to the explanatory notes in the following list:

1.

SYSDATE

sets the column to the current system date. See Setting a Column to the Current Date on page 6-56.

2.

POSITION

specifies the position of a data field. See Specifying the Position of a

Data Field on page 6-3.

INTEGER EXTERNAL is the datatype for the field. See Specifying the Datatype of a Data Field on page 6-7 and Numeric EXTERNAL on page 6-19.

The NULLIF clause is one of the clauses that can be used to specify field conditions. See Using the WHEN, NULLIF, and DEFAULTIF Clauses on page 6-32.

3.

4.

In this sample, the field is being compared to blanks, using the BLANKS parameter. See Comparing Fields to BLANKS on page 6-31.

The TERMINATED BY WHITESPACE clause is one of the delimiters it is possible to specify for a field. See TERMINATED Fields on page 6-25.

The ENCLOSED BY clause is another possible field delimiter. See Enclosed Fields on page 6-49.

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Specifying the Position of a Data Field

Specifying the Position of a Data Field

To load data from the datafile, SQL*Loader must know the length and location of the field. To specify the position of a field in the logical record, use the POSITION clause in the column specification. The position may either be stated explicitly or relative to the preceding field. Arguments to POSITION must be enclosed in parentheses. The start, end, and integer values are always in bytes, even if character-length semantics are used for a datafile.

The syntax for the position specification (pos_spec) clause is as follows: start

:

– end

( )

+integer

*

Table 6–1 describes the parameters for the position specification clause.

Table 6–1 Parameters for the Position Specification Clause

Parameter

start end

*

+ integer

Description

The starting column of the data field in the logical record. The first byte position in a logical record is 1.

The ending position of the data field in the logical record.

Either start

end

or start:end

is acceptable. If you omit end, the length of the field is derived from the datatype in the datafile. Note that CHAR data specified without start or end, and without a length specification (CHAR( n

)), is assumed to have a length of 1. If it is impossible to derive a length from the datatype, an error message is issued.

Specifies that the data field follows immediately after the previous field. If you use

*

for the first data field in the control file, that field is assumed to be at the beginning of the logical record. When you use

*

to specify position, the length of the field is derived from the datatype.

You can use an offset, specified as + integer

, to offset the current field from the next position after the end of the previous field. A number of bytes, as specified by

+integer are skipped before reading the value for the current field.

,

Field List Reference

6-3

Specifying the Position of a Data Field

You may omit POSITION entirely. If you do, the position specification for the data field is the same as if POSITION(*) had been used.

Using POSITION with Data Containing Tabs

When you are determining field positions, be alert for tabs in the datafile. The following situation is highly likely when you use the SQL*Loader advanced SQL string capabilities to load data from a formatted report:

■

You look at a printed copy of the report, carefully measuring all character positions, and create your control file.

■

The load fails with multiple "invalid number" and "missing field" errors.

These kinds of errors occur when the data contains tabs. When printed, each tab expands to consume several columns on the paper. In the datafile, however, each tab is still only one character. As a result, when SQL*Loader reads the datafile, the

POSITION

specifications are wrong.

To fix the problem, inspect the datafile for tabs and adjust the POSITION specifications, or else use delimited fields.

See Also:

Specifying Delimiters on page 6-24

Using POSITION with Multiple Table Loads

In a multiple table load, you specify multiple INTO TABLE clauses. When you specify POSITION(*) for the first column of the first table, the position is calculated relative to the beginning of the logical record. When you specify

POSITION(*)

for the first column of subsequent tables, the position is calculated relative to the last column of the last table loaded.

Thus, when a subsequent INTO TABLE clause begins, the position is not set to the beginning of the logical record automatically. This allows multiple INTO TABLE clauses to process different parts of the same physical record. For an example, see

Extracting Multiple Logical Records on page 5-39.

A logical record might contain data for one of two tables, but not both. In this case, you would reset POSITION. Instead of omitting the position specification or using

POSITION(*+ n)

for the first field in the INTO TABLE clause, use POSITION(1) or POSITION(n).

Examples of Using POSITION

siteid POSITION (*) SMALLINT

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Specifying Columns and Fields siteloc POSITION (*) INTEGER

If these were the first two column specifications, siteid would begin in column 1, and siteloc would begin in the column immediately following.

ename POSITION (1:20) CHAR empno POSITION (22-26) INTEGER EXTERNAL allow POSITION (*+2) INTEGER EXTERNAL TERMINATED BY "/"

Column ename is character data in positions 1 through 20, followed by column empno

, which is presumably numeric data in columns 22 through 26. Column allow

is offset from the next position (27) after the end of empno by +2, so it starts in column 29 and continues until a slash is encountered.

Specifying Columns and Fields

You may load any number of a table’s columns. Columns defined in the database, but not specified in the control file, are assigned null values.

A column specification is the name of the column, followed by a specification for the value to be put in that column. The list of columns is enclosed by parentheses and separated with commas as follows:

( columnspec,columnspec, ...

)

Each column name must correspond to a column of the table named in the INTO

TABLE

clause. A column name must be enclosed in quotation marks if it is a SQL or

SQL*Loader reserved word, contains special characters, or is case sensitive.

If the value is to be generated by SQL*Loader, the specification includes the

RECNUM

, SEQUENCE, or CONSTANT parameter. See Using SQL*Loader to Generate

Data for Input on page 6-54.

If the column’s value is read from the datafile, the data field that contains the column’s value is specified. In this case, the column specification includes a column

name that identifies a column in the database table, and a field specification that describes a field in a data record. The field specification includes position, datatype, null restrictions, and defaults.

It is not necessary to specify all attributes when loading column objects. Any missing attributes will be set to NULL.

Field List Reference

6-5

Specifying Columns and Fields

Specifying Filler Fields

A filler field, specified by FILLER, is a datafile mapped field that does not correspond to a database column. Filler fields are assigned values from the data fields to which they are mapped.

Keep the following in mind with regard to filler fields:

■

The syntax for a filler field is same as that for a column-based field, except that a filler field's name is followed by FILLER.

■

■

Filler fields have names but they are not loaded into the table.

Filler fields can be used as arguments to init_specs (for example, NULLIF and DEFAULTIF).

■

■

■

■

■

■

Filler fields can be used as arguments to directives (for example, SID, OID, REF,

BFILE

).

Filler fields can be used in field condition specifications in NULLIF, DEFAULTIF, and WHEN clauses. However, they cannot be used in SQL strings.

Filler field specifications cannot contain a NULLIF or DEFAULTIF clause.

Filler fields are initialized to NULL if TRAILING NULLCOLS is specified and applicable. If another field references a nullified filler field, an error is generated.

Filler fields can occur anyplace in the datafile, including inside the field list for an object or inside the definition of a VARRAY.

SQL strings cannot be specified as part of a filler field specification because no space is allocated for fillers in the bind array.

Note:

The information in this section also applies to specifying bound fillers by using BOUNDFILLER. The only exception is that with bound fillers, SQL strings can be specified as part of the field because space is allocated for them in the bind array.

A sample filler field specification looks as follows:

field_1_count FILLER char,

field_1 varray count(field_1_count)

(

filler_field1 char(2),

field_1 column object

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SQL*Loader Datatypes

(

attr1 char(2),

filler_field2 char(2),

attr2 char(2),

)

filler_field3 char(3),

)

filler_field4 char(6)

Specifying the Datatype of a Data Field

The datatype specification of a field tells SQL*Loader how to interpret the data in the field. For example, a datatype of INTEGER specifies binary data, while INTEGER

EXTERNAL

specifies character data that represents a number. A CHAR field can contain any character data.

Only one datatype can be specified for each field; if a datatype is not specified, CHAR is assumed.

SQL*Loader Datatypes on page 6-7 describes how SQL*Loader datatypes are converted into Oracle datatypes and gives detailed information on each

SQL*Loader datatype.

Before you specify the datatype, you must specify the position of the field.

SQL*Loader Datatypes

SQL*Loader datatypes can be grouped into portable and nonportable datatypes.

Within each of these two groups, the datatypes are subgrouped into value datatypes and length-value datatypes.

Portable versus nonportable refers to whether or not the datatype is platform dependent. Platform dependency can exist for a number of reasons, including differences in the byte ordering schemes of different platforms (big endian versus little endian), differences in the number of bits in a platform (16-bit, 32-bit, 64-bit), differences in signed number representation schemes (2’s complement versus 1’s complement), and so on. In some cases, such as with byte ordering schemes and platform word length, SQL*Loader provides mechanisms to help overcome platform dependencies. These mechanisms are discussed in the descriptions of the appropriate datatypes.

Both portable and nonportable datatypes can be values or length-values. Value datatypes assume that a data field has a single part. Length-value datatypes require

Field List Reference

6-7

SQL*Loader Datatypes that the data field consist of two subfields where the length subfield specifies how long the value subfield can be.

Nonportable Datatypes

Nonportable datatypes are grouped into value datatypes and length-value datatypes. The nonportable value datatypes are as follows:

■

INTEGER

(n)

■

SMALLINT

■

FLOAT

DOUBLE

■

■

■

BYTEINT

■

■

ZONED

■

(packed) DECIMAL

The nonportable length-value datatypes are as follows:

VARGRAPHIC

VARCHAR

■

VARRAW

■

LONG VARRAW

The syntax for the nonportable datatypes is shown in the syntax diagram for datatype_spec on page A-9.

INTEGER( n)

The data is a full-word binary integer, where n is an optionally supplied length of 1,

2, 4, or 8. If no length specification is given, then the length, in bytes, is based on the size of a LONG INT in the C programming language on your particular platform.

INTEGER s are not portable because their byte size, their byte order, and the representation of signed values may be different between systems. However, if the representation of signed values is the same between systems, SQL*Loader may be able to access INTEGER data with correct results. If INTEGER is specified with a length specification (n), and the appropriate technique is used (if necessary) to indicate the byte order of the data, then SQL*Loader can access the data with correct results between systems. If INTEGER is specified without a length specification, then SQL*Loader can access the data with correct results only if the

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SQL*Loader Datatypes size of a LONG INT in the C programming language is the same length in bytes on both systems. In that case, the appropriate technique must still be used (if necessary) to indicated the byte order of the data.

Specifying an explicit length for binary integers is useful in situations where the input data was created on a platform whose word length differs from that on which

SQL*Loader is running. For instance, input data containing binary integers might be created on a 64-bit platform and loaded into a database using SQL*Loader on a

32-bit platform. In this case, use INTEGER(8) to instruct SQL*Loader to process the integers as 8-byte quantities, not as 4-byte quantities.

By default, INTEGER is treated as a SIGNED quantity. If you want SQL*Loader to treat it as an unsigned quantity, specify UNSIGNED. To return to the default behavior, specify SIGNED.

See Also:

Loading Data Across Different Platforms on page 6-36

SMALLINT

The data is a half-word binary integer. The length of the field is the length of a half-word integer on your system. By default, it is treated as a SIGNED quantity. If you want SQL*Loader to treat it as an unsigned quantity, specify UNSIGNED. To return to the default behavior, specify SIGNED.

SMALLINT can be loaded with correct results only between systems where a SHORT

INT

has the same length in bytes. If the byte order is different between the systems, use the appropriate technique to indicate the byte order of the data. See Byte

Ordering on page 6-37.

Note:

This is the SHORT INT datatype in the C programming language. One way to determine its length is to make a small control file with no data and look at the resulting log file. This length cannot be overridden in the control file. See your Oracle operating system-specific documentation for details.

FLOAT

The data is a single-precision, floating-point, binary number. If you specify end in the POSITION clause, end is ignored. The length of the field is the length of a single-precision, floating-point binary number on your system. (The datatype is

FLOAT

in C.) This length cannot be overridden in the control file.

Field List Reference

6-9

SQL*Loader Datatypes

FLOAT

can be loaded with correct results only between systems where the representation of a FLOAT is compatible and of the same length. If the byte order is different between the two systems, use the appropriate technique to indicate the byte order of the data. See Byte Ordering on page 6-37.

DOUBLE

The data is a double-precision, floating-point binary number. If you specify end in the POSITION clause, end is ignored. The length of the field is the length of a double-precision, floating-point binary number on your system. (The datatype is

DOUBLE

or LONG FLOAT in C.) This length cannot be overridden in the control file.

DOUBLE

can be loaded with correct results only between systems where the representation of a DOUBLE is compatible and of the same length. If the byte order is different between the two systems, use the appropriate technique to indicate the byte order of the data. See Byte Ordering on page 6-37.

BYTEINT

The decimal value of the binary representation of the byte is loaded. For example, the input character x"1C" is loaded as 28. The length of a BYTEINT field is always 1 byte. If POSITION(start:end) is specified, end is ignored. (The datatype is

UNSIGNED CHAR

in C.)

An example of the syntax for this datatype is:

(column1 position(1) BYTEINT, column2 BYTEINT,

...

)

ZONED

ZONED

data is in zoned decimal format: a string of decimal digits, one per byte, with the sign included in the last byte. (In COBOL, this is a SIGN TRAILING field.)

The length of this field is equal to the precision (number of digits) that you specify.

The syntax for the ZONED datatype is:

, scale

ZONED ( precision )

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SQL*Loader Datatypes

In this syntax, precision is the number of digits in the number, and scale (if given) is the number of digits to the right of the (implied) decimal point. The following example specifies an 8-digit integer starting at position 32: sal POSITION(32) ZONED(8),

The Oracle database server uses the VAX/VMS zoned decimal format when the zoned data is generated on an ASCII-based platform. It is also possible to load zoned decimal data that is generated on an EBCDIC-based platform. In this case,

Oracle uses the IBM format as specified in the ESA/390 Principles of Operations, version 8.1 manual. The format that is used depends on the character set encoding of the input datafile. See CHARACTERSET Parameter on page 5-19 for more information.

DECIMAL

DECIMAL

data is in packed decimal format: two digits per byte, except for the last byte, which contains a digit and sign. DECIMAL fields allow the specification of an implied decimal point, so fractional values can be represented.

The syntax for the DECIMAL datatype is:

, scale

DECIMAL ( precision )

The precision parameter is the number of digits in a value. The length of the field in bytes, as computed from digits, is (N+1)/2 rounded up.

The scale parameter is the scaling factor, or number of digits to the right of the decimal point. The default is zero (indicating an integer). The scaling factor can be greater than the number of digits but cannot be negative.

An example is: sal DECIMAL (7,2)

This example would load a number equivalent to +12345.67. In the data record, this field would take up 4 bytes. (The byte length of a DECIMAL field is equivalent to

(N+1)/2, rounded up, where N is the number of digits in the value, and 1 is added for the sign.)

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SQL*Loader Datatypes

VARGRAPHIC

The data is a varying-length, double-byte character string. It consists of a length subfield followed by a string of double-byte characters (DBCS). The Oracle database server does not support DBCS; however, SQL*Loader reads DBCS as single bytes and loads it as RAW data. Like RAW data, VARGRAPHIC fields are stored without modification in whichever column you specify.

Note:

The size of the length subfield is the size of the SQL*Loader

SMALLINT

datatype on your system (C type SHORT INT). See

SMALLINT on page 6-9 for more information.

VARGRAPHIC data can be loaded with correct results only between systems where a

SHORT INT

has the same length in bytes. If the byte order is different between the systems, use the appropriate technique to indicate the byte order of the length subfield. See Byte Ordering on page 6-37.

The syntax for the VARGRAPHIC datatype is:

( max_length )

VARGRAPHIC

The length of the current field is given in the first 2 bytes. A maximum length specified for the VARGRAPHIC datatype does not include the size of the length subfield. The maximum length specifies the number of graphic (double-byte) characters. It is multiplied by 2 to determine the maximum length of the field in bytes.

The default maximum field length is 2 KB graphic characters, or 4 KB

(2 * 2KB). To minimize memory requirements, specify a maximum length for such fields whenever possible.

If a position specification is specified (using pos_spec) before the VARGRAPHIC statement, it provides the location of the length subfield, not of the first graphic character. If you specify pos_spec(start:end), the end location determines a maximum length for the field. Both start and end identify single-character (byte) positions in the file. Start is subtracted from (end + 1) to give the length of the field in bytes. If a maximum length is specified, it overrides any maximum length calculated from the position specification.

If a VARGRAPHIC field is truncated by the end of the logical record before its full length is read, a warning is issued. Because the length of a VARGRAPHIC field is

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SQL*Loader Datatypes embedded in every occurrence of the input data for that field, it is assumed to be accurate.

VARGRAPHIC

data cannot be delimited.

VARCHAR

A VARCHAR field is a length-value datatype. It consists of a binary length subfield followed by a character string of the specified length. The length is in bytes unless character-length semantics are used for the datafile. In that case, the length is in characters. See Character-Length Semantics on page 5-22.

VARCHAR

fields can be loaded with correct results only between systems where a

SHORT data field INT has the same length in bytes. If the byte order is different between the systems, or if the VARCHAR field contains data in the UTF16 character set, use the appropriate technique to indicate the byte order of the length subfield and of the data. The byte order of the data is only an issue for the UTF16 character set. See Byte Ordering on page 6-37.

Note:

The size of the length subfield is the size of the SQL*Loader

SMALLINT

datatype on your system (C type SHORT INT). See

SMALLINT on page 6-9 for more information.

The syntax for the VARCHAR datatype is:

( max_length )

VARCHAR

A maximum length specified in the control file does not include the size of the length subfield. If you specify the optional maximum length for a VARCHAR datatype, then a buffer of that size, in bytes, is allocated for these fields. However, if character-length semantics are used for the datafile, the buffer size in bytes is the max

_length times the size in bytes of the largest possible character in the character set. See Character-Length Semantics on page 5-22.

The default maximum size is 4 KB. Specifying the smallest maximum length that is needed to load your data can minimize SQL*Loader’s memory requirements, especially if you have many VARCHAR fields.

The POSITION clause, if used, gives the location, in bytes, of the length subfield, not of the first text character. If you specify POSITION(start:end), the end

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SQL*Loader Datatypes location determines a maximum length for the field. Start is subtracted from (end

+ 1)

to give the length of the field in bytes. If a maximum length is specified, it overrides any length calculated from POSITION.

If a VARCHAR field is truncated by the end of the logical record before its full length is read, a warning is issued. Because the length of a VARCHAR field is embedded in every occurrence of the input data for that field, it is assumed to be accurate.

VARCHAR

data cannot be delimited.

VARRAW

VARRAW

is made up of a 2-byte binary length subfield followed by a RAW string value subfield.

VARRAW

results in a VARRAW with a 2-byte length subfield and a maximum size of 4

KB (that is, the default). VARRAW(65000) results in a VARRAW with a length subfield of 2 bytes and a maximum size of 65000 bytes.

VARRAW

fields can be loaded between systems with different byte orders if the appropriate technique is used to indicate the byte order of the length subfield. See

Byte Ordering on page 6-37.

LONG VARRAW

LONG VARRAW

is a VARRAW with a 4-byte length subfield instead of a 2-byte length subfield.

LONG VARRAW results in a VARRAW with 4-byte length subfield and a maximum size of 4 KB (that is, the default). LONG VARRAW(300000) results in a VARRAW with a length subfield of 4 bytes and a maximum size of 300000 bytes.

LONG VARRAW

fields can be loaded between systems with different byte orders if the appropriate technique is used to indicate the byte order of the length subfield.

See Byte Ordering on page 6-37.

Portable Datatypes

The portable datatypes are grouped into value datatypes and length-value datatypes. The portable value datatypes are as follows:

■

CHAR

■

Datetime and Interval

■

GRAPHIC

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■

■

GRAPHIC EXTERNAL

Numeric EXTERNAL (INTEGER, FLOAT, DECIMAL, ZONED)

■

RAW

The portable length-value datatypes are as follows:

■

VARCHARC

■

VARRAWC

The syntax for these datatypes is shown in the diagram for datatype_spec on page A-9.

The character datatypes are CHAR, DATE, and the numeric EXTERNAL datatypes.

These fields can be delimited and can have lengths (or maximum lengths) specified in the control file.

CHAR

The data field contains character data. The length, which is optional, is a maximum length. Note the following with regard to length:

■

■

■

If a length is not specified, it is derived from the POSITION specification.

If a length is specified, it overrides the length in the POSITION specification.

If no length is given and there is no position specification, CHAR data is assumed to have a length of 1, unless the field is delimited:

–

For a delimited CHAR field, if a length is specified, that length is used as a maximum.

–

For a delimited CHAR field for which no length is specified, the default is

255 bytes.

–

For a delimited CHAR field that is greater than 255 bytes, you must specify a maximum length. Otherwise you will receive an error stating that the field in the datafile exceeds maximum length.

The syntax for the CHAR datatype is:

(length) delim_spec

CHAR

See Also:

Specifying Delimiters on page 6-24

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6-15

SQL*Loader Datatypes

■

■

■

■

Datetime and Interval Datatypes

The datetime datatypes are:

DATE

TIME

TIMESTAMP

TIME WITH TIME ZONE

■

■

TIMESTAMP WITH TIME ZONE

Values of datetime datatypes are sometimes called datetimes.

The interval datatypes are:

INTERVAL YEAR TO MONTH

■

INTERVAL DAY TO SECOND

Values of interval datatypes are sometimes called intervals.

Both datetimes and intervals are made up of fields. The values of these fields determine the value of the datatype.

See Also:

Oracle9i SQL Reference for more detailed information about datetime and interval datatypes

DATE

The DATE field contains character data that should be converted to an Oracle date using the specified date mask. The syntax for the DATE field is:

(length) "mask" delim_spec

DATE

For example:

LOAD DATA

INTO TABLE dates (col_a POSITION (1:15) DATE "DD-Mon-YYYY")

BEGINDATA

1-Jan-1991

1-Apr-1991 28-Feb-1991

Whitespace is ignored and dates are parsed from left to right unless delimiters are present. (A DATE field that consists entirely of whitespace is loaded as a NULL field.)

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The length specification is optional, unless a varying-length date mask is specified.

The length is in bytes unless character-length semantics are used for the datafile. In that case, the length is in characters. See Character-Length Semantics on page 5-22.

In the preceding example, the date mask, "DD-Mon-YYYY" contains 11 bytes, with byte-length semantics. Therefore, SQL*Loader expects a maximum of 11 bytes in the field, so the specification works properly. But, suppose a specification such as the following is given:

DATE "Month dd, YYYY"

In this case, the date mask contains 14 bytes. If a value with a length longer than 14 bytes is specified, such as "September 30, 1991", a length must be specified.

Similarly, a length is required for any Julian dates (date mask "J"). A field length is required any time the length of the date string could exceed the length of the mask

(that is, the count of bytes in the mask).

If an explicit length is not specified, it can be derived from the POSITION clause. It is a good idea to specify the length whenever you use a mask, unless you are absolutely sure that the length of the data is less than, or equal to, the length of the mask.

An explicit length specification, if present, overrides the length in the POSITION clause. Either of these overrides the length derived from the mask. The mask may be any valid Oracle date mask. If you omit the mask, the default Oracle date mask of "dd-mon-yy" is used.

The length must be enclosed in parentheses and the mask in quotation marks.

Case

Study 3: Loading a Delimited, Free-Format File on page 10-11 provides an example of the DATE datatype.

A field of datatype DATE may also be specified with delimiters. For more information, see Specifying Delimiters on page 6-24.

TIME

The TIME datatype stores hour, minute, and second values. For example:

09:26:50

TIMESTAMP

The TIMESTAMP datatype is an extension of the DATE datatype. It stores the year, month, and day of the DATE datatype, plus the hour, minute, and second values of the TIME datatype. An example TIMESTAMP is as follows:

TIMESTAMP ’1999-01-31 09:26:50’

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SQL*Loader Datatypes

If you specify a date value without a time component, the default time is 12:00:00

AM (midnight).

TIME WITH TIME ZONE

The TIME WITH TIME ZONE datatype is a variant of TIME that includes a time zone displacement in its value. The time zone displacement is the difference (in hours and minutes) between local time and UTC (coordinated universal time, formerly Greenwich mean time).

If the LOCAL option is specified, then data stored in the database is normalized to the database time zone, and time zone displacement is not stored as part of the column data. When the data is retrieved, it is returned in the user’s local session time zone.

TIMESTAMP WITH TIME ZONE

The TIMESTAMP WITH TIME ZONE datatype is a variant of TIMESTAMP that includes a time zone displacement in its value. The time zone displacement is the difference (in hours and minutes) between local time and

UTC (coordinated universal time, formerly Greenwich mean time).

If the LOCAL option is specified, then data stored in the database is normalized to the database time zone, and time zone displacement is not stored as part of the column data. When the data is retrieved, it is returned in the user’s local session time zone.

INTERVAL YEAR TO MONTH

The INTERVAL YEAR TO MONTH datatype stores a period of time using the YEAR and MONTH datetime fields.

INTERVAL DAY TO SECOND

The INTERVAL DAY TO SECOND datatype stores a period of time using the DAY and SECOND datetime fields.

GRAPHIC

The data is a string of double-byte characters (DBCS). The Oracle database server does not support DBCS; however, SQL*Loader reads DBCS as single bytes. Like

RAW data, GRAPHIC fields are stored without modification in whichever column you specify.

The syntax for the GRAPHIC datatype is:

(graphic_char_length)

GRAPHIC

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For GRAPHIC and GRAPHIC EXTERNAL, specifying POSITION(start:end) gives the exact location of the field in the logical record.

If you specify a length for the GRAPHIC (EXTERNAL) datatype, however, then you give the number of double-byte graphic characters. That value is multiplied by 2 to find the length of the field in bytes. If the number of graphic characters is specified, then any length derived from POSITION is ignored. No delimited data field specification is allowed with GRAPHIC datatype specification.

GRAPHIC EXTERNAL

If the DBCS field is surrounded by shift-in and shift-out characters, use GRAPHIC

EXTERNAL

. This is identical to GRAPHIC, except that the first and last characters

(the shift-in and shift-out) are not loaded.

The syntax for the GRAPHIC EXTERNAL datatype is:

(graphic_char_length)

GRAPHIC EXTERNAL

GRAPHIC indicates that the data is double-byte characters. EXTERNAL indicates that the first and last characters are ignored. The graphic_char_length value specifies the length in DBCS (see GRAPHIC on page 6-18).

For example, let [ ] represent shift-in and shift-out characters, and let # represent any double-byte character.

To describe ####, use POSITION(1:4) GRAPHIC or POSITION(1) GRAPHIC(2).

To describe [####], use POSITION(1:6) GRAPHIC EXTERNAL or POSITION(1)

GRAPHIC EXTERNAL(2)

.

Numeric EXTERNAL

The numeric EXTERNAL datatypes are the numeric datatypes (INTEGER, FLOAT,

DECIMAL,

and ZONED) specified as EXTERNAL, with optional length and delimiter specifications. The length is in bytes unless character-length semantics are used for the datafile. In that case, the length is in characters. See Character-Length Semantics on page 5-22.

These datatypes are the human-readable, character form of numeric data. The same rules that apply to CHAR data with regard to length, position, and delimiters apply to numeric EXTERNAL data. See CHAR on page 6-15 for a complete description of these rules.

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SQL*Loader Datatypes

The syntax for the numeric EXTERNAL datatypes is shown as part of datatype_spec on page A-9.

Note:

The data is a number in character form, not binary representation. Therefore, these datatypes are identical to CHAR and are treated identically, except for the use of DEFAULTIF. If you want the default to be null, use CHAR; if you want it to be zero, use

EXTERNAL

. See Using the WHEN, NULLIF, and DEFAULTIF

Clauses on page 6-32.

FLOAT EXTERNAL

data can be given in either scientific or regular notation. Both

"5.33" and "533E-2" are valid representations of the same value.

RAW

When raw, binary data is loaded "as is" into a RAW database column, it is not converted by the Oracle database server. If it is loaded into a CHAR column, the

Oracle database server converts it to hexadecimal. It cannot be loaded into a DATE or number column.

The syntax for the RAW datatype is as follows:

(length)

RAW

The length of this field is the number of bytes specified in the control file. This length is limited only by the length of the target column in the database and by memory resources. The length is always in bytes, even if character-length semantics are used for the datafile. RAW data fields cannot be delimited.

VARCHARC

The datatype VARCHARC consists of a character length subfield followed by a character string value-subfield.

The declaration for VARCHARC specifies the length of the length subfield, optionally followed by the maximum size of any string. If byte-length semantics are in use for the datafile, then the length and the maximum size are both in bytes. If character-length semantics are in use for the datafile, then the length and maximum size are in characters. If a maximum size is not specified, 4 KB is the default

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SQL*Loader Datatypes regardless of whether byte-length semantics or character-length semantics are in use.

For example:

■

VARCHARC

results in an error because you must at least specify a value for the length subfield.

■

VARCHARC(7) results in a VARCHARC whose length subfield is 7 bytes long and whose maximum size is 4 KB (the default) if byte-length semantics are used for the datafile. If character-length semantics are used, it results in a VARCHARC with a length subfield that is 7 characters long and a maximum size of 4 KB (the default). Remember that when a maximum size is not specified, the default of 4

KB is always used, regardless of whether byte-length or character-length semantics are in use.

■

VARCHARC(3,500)

results in a VARCHARC whose length subfield is 3 bytes long and whose maximum size is 500 bytes if byte-length semantics are used for the datafile. If character-length semantics are used, it results in a VARCHARC with a length subfield that is 3 characters long and a maximum size of 500 characters.

See Character-Length Semantics on page 5-22.

VARRAWC

The datatype VARRAWC consists of a RAW string value subfield.

For example:

■

VARRAWC

results in an error.

■

■

VARRAWC(7)

results in a VARRAWC whose length subfield is 7 bytes long and whose maximum size is 4 KB (that is, the default).

VARRAWC(3,500)

results in a VARRAWC whose length subfield is 3 bytes long and whose maximum size is 500 bytes.

Conflicting Native Datatype Field Lengths

There are several ways to specify a length for a field. If multiple lengths are specified and they conflict, then one of the lengths takes precedence. A warning is issued when a conflict exists. The following rules determine which field length is used:

1.

The size of SMALLINT, FLOAT, and DOUBLE data is fixed, regardless of the number of bytes specified in the POSITION clause.

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SQL*Loader Datatypes

2.

If the length specified (or precision) of a DECIMAL, INTEGER, ZONED, GRAPHIC,

GRAPHIC EXTERNAL

, or RAW field conflicts with the size calculated from a

POSITION (start:end)

specification, then the specified length (or precision) is used.

3.

If the maximum size specified for a character or VARGRAPHIC field conflicts with the size calculated from a POSITION(start:end) specification, then the specified maximum is used.

For example, assume that the native datatype INTEGER is 4 bytes long and the following field specification is given: column1 POSITION(1:6) INTEGER

In this case, a warning is issued, and the proper length (4) is used. The log file shows the actual length used under the heading "Len" in the column table:

Column Name Position Len Term Encl Datatype

----------------------- --------- ----- ---- ---- ---------

COLUMN1 1:6 4 INTEGER

Field Lengths for Length-Value Datatypes

A control file can specify a maximum length for the following length-value datatypes: VARCHAR, VARCHARC, VARGRAPHIC, VARRAW, and VARRAWC. The specified maximum length is in bytes if byte-length semantics are used for the field, and in characters if character-length semantics are used for the field. If no length is specified, the maximum length defaults to 4096 bytes. If the length of the field exceeds the maximum length, the record is rejected with the following error:

Variable length field exceed maximum length

Datatype Conversions

The datatype specifications in the control file tell SQL*Loader how to interpret the information in the datafile. The server defines the datatypes for the columns in the database. The link between these two is the column name specified in the control file.

SQL*Loader extracts data from a field in the input file, guided by the datatype specification in the control file. SQL*Loader then sends the field to the server to be stored in the appropriate column (as part of an array of row inserts).

SQL*Loader or the server does any necessary data conversion to store the data in the proper internal format. This includes converting data from the datafile character set to the database character set when they differ.

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The datatype of the data in the file does not need to be the same as the datatype of the column in the Oracle table. The Oracle database server automatically performs conversions, but you need to ensure that the conversion makes sense and does not generate errors. For instance, when a datafile field with datatype CHAR is loaded into a database column with datatype NUMBER, you must make sure that the contents of the character field represent a valid number.

Note:

SQL*Loader does not contain datatype specifications for

Oracle internal datatypes such as NUMBER or VARCHAR2. The

SQL*Loader datatypes describe data that can be produced with text editors (character datatypes) and with standard programming languages (native datatypes). However, although SQL*Loader does not recognize datatypes like NUMBER and VARCHAR2, any data that the Oracle database server is capable of converting may be loaded into these or other database columns.

Datatype Conversions for Datetime and Interval Datatypes

Table 6–2 shows which conversions between Oracle database datatypes and

SQL*Loader control file datetime and interval datatypes are supported and which are not.

In the table, the abbreviations for the Oracle Database Datatypes are as follows:

N = NUMBER

C = CHAR or VARCHAR2

D = DATE

T = TIME and TIME WITH TIME ZONE

TS = TIMESTAMP and TIMESTAMP WITH TIME ZONE

YM = INTERVAL YEAR TO MONTH

DS = INTERVAL DAY TO SECOND

For the SQL*Loader datatypes, the definitions for the abbreviations in the table are the same for D, T, TS, YM, and DS. However, as noted in the previous section,

SQL*Loader does not contain datatype specifications for Oracle internal datatypes such as NUMBER,CHAR, and VARCHAR2. However, any data that the Oracle database server is capable of converting can be loaded into these or other database columns.

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SQL*Loader Datatypes

For an example of how to read this table, look at the row for the SQL*Loader datatype DATE (abbreviated as D). Reading across the row, you can see that datatype conversion is supported for the Oracle database datatypes of CHAR,

VARCHAR2

, DATE, TIMESTAMP, and TIMESTAMP WITH TIMEZONE datatypes.

However, conversion is not supported for the Oracle database datatypes NUMBER,

TIME

, TIME WITH TIME ZONE, INTERVAL YEAR TO MONTH, or INTERVAL DAY TO

SECOND

datatypes.

Table 6–2 Datatype Conversions for Datetime and Interval Datatypes

SQL*Loader Datatype

D

T

N

C

TS

YM

DS

Oracle Database Datatype (Conversion Support)

N

(Yes), C (Yes), D (No), T (No), TS (No), YM (No), DS (No)

N

(Yes), C (Yes), D (Yes), T (Yes), TS (Yes), YM (Yes), DS (Yes)

N

(No), C (Yes), D (Yes), T (No), TS (Yes), YM (No), DS (No)

N

(No), C (Yes), D (No), T (Yes), TS (Yes), YM (No), DS (No)

N

(No), C (Yes), D (Yes), T (Yes), TS (Yes), YM (No), DS (No)

N

(No), C (Yes), D (No), T (No), TS (No), YM (Yes), DS (No)

N

(No), C (Yes), D (No), T (No), TS (No), YM (No), DS (Yes)

Specifying Delimiters

The boundaries of CHAR, datetime, interval, or numeric EXTERNAL fields may also be marked by specific delimiter characters contained in the input data record. The

RAW

datatype may also be marked by delimiters, but only if it is in an input

LOBFILE, and only if the delimiter is TERMINATED BY EOF (end of file). You indicate how the field is delimited by using a delimiter specification after specifying the datatype.

Delimited data can be terminated or enclosed, as shown in the following syntax: enclosure_spec

OPTIONALLY enclosure_spec termination_spec

You can specify a TERMINATED BY clause, an ENCLOSED BY clause, or both. If both are used, the TERMINATED BY clause must come first.

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TERMINATED Fields

TERMINATED

fields are read from the starting position of the field up to, but not including, the first occurrence of the delimiter character. If the terminator delimiter is found in the first column position, the field is null.

If TERMINATED BY WHITESPACE is specified, data is read until the first occurrence of a whitespace character (spaces, tabs, blanks, line feeds, form feeds, or carriage returns). Then the current position is advanced until no more adjacent whitespace characters are found. This allows field values to be delimited by varying amounts of whitespace. For more information about the syntax, see Syntax for Termination and

Enclosure Specification on page 6-25.

ENCLOSED Fields

ENCLOSED

fields are read by skipping whitespace until a nonwhitespace character is encountered. If that character is the delimiter, then data is read up to the second delimiter. Any other character causes an error.

If two delimiter characters are encountered next to each other, a single occurrence of the delimiter character is used in the data value. For example, ’DON’’T’ is stored as

DON’T. However, if the field consists of just two delimiter characters, its value is null. For more information about the syntax, see Syntax for Termination and

Enclosure Specification on page 6-25.

Syntax for Termination and Enclosure Specification

TERMINATED

BY

WHITESPACE

X’hexstr’

’string’

EOF

BY

’string’

X’hexstr’

AND

’string’

X’hexstr’

ENCLOSED

Table 6–3 describes the syntax for the termination and enclosure specification.

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SQL*Loader Datatypes

Table 6–3 Parameters for Termination and Enclosure Specification

Parameter

TERMINATED

BY

WHITESPACE

OPTIONALLY

ENCLOSED string

X’hexstr

AND

EOF

’

Description

Data is read until the first occurrence of a delimiter.

An optional word to increase readability.

Delimiter is any whitespace character including spaces, tabs, blanks, line feeds, form feeds, or carriage returns. (Only used with TERMINATED, not with ENCLOSED.)

Data can be enclosed by the specified character. If SQL*Loader finds a first occurrence of the character, it reads the data value until it finds the second occurrence. If the data is not enclosed, the data is read as a terminated field. If you specify an optional enclosure, you must specify a TERMINATED BY clause (either locally in the field definition or globally in the FIELDS clause).

The data will be found between two delimiters.

The delimiter is a string.

The delimiter is a string that has the value specified by

X’hexstr’

in the character encoding scheme, such as X’1F’

(equivalent to 31 decimal). "X"can be either lowercase or uppercase.

Specifies a trailing enclosure delimiter that may be different from the initial enclosure delimiter. If AND is not present, then the initial and trailing delimiters are assumed to be the same.

Indicates that the entire file has been loaded into the LOB. This is valid only when data is loaded from a LOB file. Fields terminated by EOF cannot be enclosed.

Here are some examples, with samples of the data they describe:

TERMINATED BY ’,’ a data string,

ENCLOSED BY ’"’ "a data string"

TERMINATED BY ’,’ ENCLOSED BY ’"’ "a data string",

ENCLOSED BY ’(’ AND ’)’ (a data string)

Delimiter Marks in the Data

Sometimes the punctuation mark that is a delimiter must also be included in the data. To make that possible, two adjacent delimiter characters are interpreted as a single occurrence of the character, and this character is included in the data. For example, this data:

(The delimiters are left parentheses, (, and right parentheses, )).)

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SQL*Loader Datatypes with this field specification:

ENCLOSED BY "(" AND ")" puts the following string into the database:

The delimiters are left parentheses, (, and right parentheses, ).

For this reason, problems can arise when adjacent fields use the same delimiters.

For example, with the following specification: field1 TERMINATED BY "/" field2 ENCLOSED by "/" the following data will be interpreted properly:

This is the first string/ /This is the second string/

But if field1 and field2 were adjacent, then the results would be incorrect, because

This is the first string//This is the second string/ would be interpreted as a single character string with a "/" in the middle, and that string would belong to field1.

Maximum Length of Delimited Data

The default maximum length of delimited data is 255 bytes. Therefore, delimited fields can require significant amounts of storage for the bind array. A good policy is to specify the smallest possible maximum value if the fields are shorter than 255 bytes. If the fields are longer than 255 bytes, then you must specify a maximum length for the field, either with a length specifier or with the POSITION clause.

Loading Trailing Blanks with Delimiters

Trailing blanks are not loaded with nondelimited datatypes unless you specify

PRESERVE BLANKS

. If a data field is 9 characters long and contains the value

DANIEL bbb

, where bbb is three blanks, it is loaded into the Oracle database as

"DANIEL" if declared as CHAR(9).

If you want the trailing blanks, you could declare it as CHAR(9) TERMINATED BY

’:’

, and add a colon to the datafile so that the field is DANIELbbb:. This field is loaded as "DANIEL ", with the trailing blanks. You could also specify

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SQL*Loader Datatypes

PRESERVE BLANKS

without the TERMINATED BY clause and obtain the same results.

See Also:

■

■

Trimming Whitespace on page 6-42

Preserving Whitespace on page 6-49

Conflicting Field Lengths for Character Datatypes

A control file can specify multiple lengths for the character-data fields CHAR, DATE, and numeric EXTERNAL. If conflicting lengths are specified, one of the lengths takes precedence. A warning is also issued when a conflict exists. This section explains which length is used.

Predetermined Size Fields

If you specify a starting position and ending position for one of these fields, then the length of the field is determined by these specifications. If you specify a length as part of the datatype and do not give an ending position, the field has the given length. If starting position, ending position, and length are all specified, and the lengths differ, then the length given as part of the datatype specification is used for the length of the field, as follows:

POSITION(1:10) CHAR(15)

In this example, the length of the field is 15.

Delimited Fields

If a delimited field is specified with a length, or if a length can be calculated from the starting and ending positions, then that length is the maximum length of the field. The specified maximum length is in bytes if byte-length semantics are used for the field, and in characters if character-length semantics are used for the field. If no length is specified or can be calculated from the start and end positions, the maximum length defaults to 255 bytes. The actual length can vary up to that maximum, based on the presence of the delimiter.

If starting and ending positions are specified for the field, as well as delimiters, then only the position specification has any effect. Any enclosure or termination delimiters are ignored.

If the expected delimiter is absent, then the end of record terminates the field. If

TRAILING NULLCOLS

is specified, remaining fields are null. If either the delimiter

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Specifying Field Conditions or the end of record produces a field that is longer than the maximum, SQL*Loader rejects the record and returns and error.

Date Field Masks

The length of a date field depends on the mask, if a mask is specified. The mask provides a format pattern, telling SQL*Loader how to interpret the data in the record. For example, assume the mask is specified as follows:

"Month dd, yyyy"

Then "May 3, 1991" would occupy 11 bytes in the record (with byte-length semantics), while "January 31, 1992" would occupy 16.

If starting and ending positions are specified, however, then the length calculated from the position specification overrides a length derived from the mask. A specified length such as DATE(12) overrides either of those. If the date field is also specified with terminating or enclosing delimiters, then the length specified in the control file is interpreted as a maximum length for the field.

See Also:

Datetime and Interval Datatypes on page 6-16 for more information on the DATE field

Specifying Field Conditions

A field condition is a statement about a field in a logical record that evaluates as true or false. It is used in the NULLIF and DEFAULTIF clauses, as well as in the

WHEN

clause.

A field condition is similar to the condition in the CONTINUEIF clause, with two important differences. First, positions in the field condition refer to the logical record, not to the physical record. Second, you can specify either a position in the logical record or the name of a field in the datafile (including filler fields).

Note:

A field condition cannot be based on fields in a secondary datafile (SDF).

The syntax for the field_condition clause is as follows:

Field List Reference

6-29

Specifying Field Conditions

AND

( full_fieldname pos_spec operator

’char_string’

X’hex_string’

BLANKS

The syntax for the pos_spec clause is as follows: start

:

– end

(

+integer

*

)

)

Table 6–4 describes the parameters used for the field condition clause. For a full description of the position specification parameters, see Table 6–1 .

Table 6–4 Parameters for the Field Condition Clause

Parameter

pos_spec start end

Description

Specifies the starting and ending position of the comparison field in the logical record. It must be surrounded by parentheses. Either start

end

or start

: end

is acceptable.

The starting location can be specified as a column number, or as

*

(next column), or as

*+n

(next column plus an offset).

If you omit an ending position, the length of the field is determined by the length of the comparison string. If the lengths are different, the shorter field is padded. Character strings are padded with blanks, hexadecimal strings with zeros.

Specifies the starting position of the comparison field in the logical record.

Specifies the ending position of the comparison field in the logical record.

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Specifying Field Conditions

Table 6–4 (Cont.) Parameters for the Field Condition Clause

Parameter

full_fieldname operator char_string

X’hex_string

BLANKS

’

Description

full_fieldname

is the full name of a field specified using dot notation. If the field col2 is an attribute of a column object col1

, when referring to col2

in one of the directives, you must use the notation col1

.

col2

. The column name and the field name referencing or naming the same entity can be different, because the column name never includes the full name of the entity (no dot notation).

A comparison operator for either equal or not equal.

A string of characters enclosed in single or double quotation marks that is compared to the comparison field. If the comparison is true, the current record is inserted into the table.

A string of hexadecimal digits, where each pair of digits corresponds to one byte in the field. It is enclosed in single or double quotation marks. If the comparison is true, the current record is inserted into the table.

Allows you to test a field to see if it consists entirely of blanks.

BLANKS

is required when you are loading delimited data and you cannot predict the length of the field, or when you use a multibyte character set that has multiple blanks.

Comparing Fields to BLANKS

The BLANKS parameter makes it possible to determine if a field of unknown length is blank.

For example, use the following clause to load a blank field as null: full_fieldname ... NULLIF column_name =BLANKS

The BLANKS parameter recognizes only blanks, not tabs. It can be used in place of a literal string in any field comparison. The condition is true whenever the column is entirely blank.

The BLANKS parameter also works for fixed-length fields. Using it is the same as specifying an appropriately sized literal string of blanks. For example, the following specifications are equivalent: fixed_field

CHAR(2) NULLIF fixed_field

=BLANKS fixed_field CHAR(2) NULLIF fixed_field =" "

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Using the WHEN, NULLIF, and DEFAULTIF Clauses

There can be more than one blank in a multibyte character set. It is a good idea to use the BLANKS parameter with these character sets instead of specifying a string of blank characters.

The character string will match only a specific sequence of blank characters, while the BLANKS parameter will match combinations of different blank characters. For more information on multibyte character sets, see Multibyte (Asian) Character Sets on page 5-17.

Comparing Fields to Literals

When a data field is compared to a literal string that is shorter than the data field, the string is padded. Character strings are padded with blanks, for example:

NULLIF (1:4)=" "

This example compares the data in position 1:4 with 4 blanks. If position 1:4 contains 4 blanks, then the clause evaluates as true.

Hexadecimal strings are padded with hexadecimal zeros, as in the following clause:

NULLIF (1:4)=X’FF’

This clause compares position 1:4 to hexadecimal ’FF000000’.

Using the WHEN, NULLIF, and DEFAULTIF Clauses

The following information applies to scalar fields. For nonscalar fields (column objects, LOBs, and collections), the WHEN, NULLIF, and DEFAULTIF clauses are processed differently because nonscalar fields are more complex.

The results of a WHEN, NULLIF, or DEFAULTIF clause can be different depending on whether the clause specifies a field name or a position.

If the WHEN, NULLIF, or DEFAULTIF clause specifies a field name, SQL*Loader compares the clause to the evaluated value of the field. The evaluated value takes trimmed whitespace into consideration. See Trimming Whitespace on page 6-42 for information about trimming blanks and tabs.

If the WHEN, NULLIF, or DEFAULTIF clause specifies a position, SQL*Loader compares the clause to the original logical record in the datafile. No whitespace trimming is done on the logical record in that case.

Different results are more likely if the field has whitespace that is trimmed, or if the

WHEN

, NULLIF, or DEFAULTIF clause contains blanks or tabs or uses the BLANKS

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Using the WHEN, NULLIF, and DEFAULTIF Clauses parameter. If you require the same results for a field specified by name and for the same field specified by position, use the PRESERVE BLANKS option. The PRESERVE

BLANKS

option instructs SQL*Loader not to trim whitespace when it evaluates the values of the fields.

The results of a WHEN, NULLIF, or DEFAULTIF clause are also affected by the order in which SQL*Loader operates, as described in the following steps. SQL*Loader performs these steps in order, but it does not always perform all of them. Once a field is set, any remaining steps in the process are ignored. For example, if the field is set in step 5, SQL*Loader does not move on to step 6.

1.

2.

3.

4.

5.

6.

SQL*Loader evaluates the value of each field for the input record and trims any whitespace that should be trimmed (according to existing guidelines for trimming blanks and tabs).

For each record, SQL*Loader evaluates any WHEN clauses for the table.

If the record satisfies the WHEN clauses for the table, or no WHEN clauses are specified, SQL*Loader checks each field for a NULLIF clause.

If a NULLIF clause exists, SQL*Loader evaluates it.

If the NULLIF clause is satisfied, SQL*Loader sets the field to NULL.

If the NULLIF clause is not satisfied, or if there is no NULLIF clause,

SQL*Loader checks the length of the field from field evaluation. If the field has a length of 0 from field evaluation (for example, it was a null field, or whitespace trimming resulted in a null field), SQL*Loader sets the field to

NULL

. In this case, any DEFAULTIF clause specified for the field is not evaluated.

7.

8.

9.

If any specified NULLIF clause is false or there is no NULLIF clause, and if the field does not have a length of 0 from field evaluation, SQL*Loader checks the field for a DEFAULTIF clause.

If a DEFAULTIF clause exists, SQL*Loader evaluates it.

If the DEFAULTIF clause is satisfied, then the field is set to 0 if the field in the datafile is a numeric field. It is set to NULL if the field is not a numeric field. The following fields are numeric fields and will be set to 0 if they satisfy the

DEFAULTIF

clause:

■

BYTEINT

■

■

SMALLINT

INTEGER

Field List Reference

6-33

Using the WHEN, NULLIF, and DEFAULTIF Clauses

■

FLOAT

■

DOUBLE

■

ZONED

■

(packed) DECIMAL

■

Numeric EXTERNAL (INTEGER, FLOAT, DECIMAL, and ZONED)

10.

If the DEFAULTIF clause is not satisfied, or if there is no DEFAULTIF clause,

SQL*Loader sets the field with the evaluated value from step 1.

The order in which SQL*Loader operates could cause results that you do not expect.

For example, the DEFAULTIF clause may look like it is setting a numeric field to

NULL

rather than to 0.

Example 6–2 through Example 6–5 clarify the results for different situations. In the examples, a blank or space is indicated with a period (.). Assume that col1 and col2

are VARCHAR2(5) columns in the database.

Example 6–2 DEFAULTIF Clause Is Not Evaluated

The control file specifies:

(col1 POSITION (1:5),

col2 POSITION (6:8) CHAR INTEGER EXTERNAL DEFAULTIF col1 = ’aname’)

The datafile contains: aname...

In Example 6–2 , col1 for the row evaluates to aname. col2 evaluates to NULL with a length of 0 (it is "..." but the trailing blanks are trimmed for a positional field).

When SQL*Loader determines the final loaded value for col2, it finds no WHEN clause and no NULLIF clause. It then checks the length of the field, which is 0 from field evaluation. Therefore, SQL*Loader sets the final value for col2 to NULL. The

DEFAULTIF

clause is not evaluated, and the row is loaded as aname for col1 and

NULL

for col2.

.

.

.

Example 6–3 DEFAULTIF Clause Is Evaluated

The control file specifies:

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Using the WHEN, NULLIF, and DEFAULTIF Clauses

PRESERVE BLANKS

.

.

.

(col1 POSITION (1:5),

col2 POSITION (6:8) INTEGER EXTERNAL DEFAULTIF col1 = ’aname’

The datafile contains: aname...

In Example 6–3 , col1 for the row again evaluates to ’aname’. col2 evaluates to

’...’ because trailing blanks are not trimmed when PRESERVE BLANKS is specified.

When SQL*Loader determines the final loaded value for col2, it finds no WHEN clause and no NULLIF clause. It then checks the length of the field from field evaluation, which is 3, not 0.

Then SQL*Loader evaluates the DEFAULTIF clause, which evaluates to true because col1 is ’aname’, which is the same as ’aname’.

Because col2 is a numeric field, SQL*Loader sets the final value for col2 to ’0’.

The row is loaded as ’aname’ for col1 and as ’0’ for col2.

Example 6–4 DEFAULTIF Clause Specifies a Position

The control file specifies:

(col1 POSITION (1:5),

col2 POSITION (6:8) INTEGER EXTERNAL DEFAULTIF (1:5) = BLANKS)

The datafile contains:

.....123

In Example 6–4 , col1 for the row evaluates to NULL with a length of 0 (it is .....

but the trailing blanks are trimmed). col2 evaluates to 123.

When SQL*Loader sets the final loaded value for col2, it finds no WHEN clause and no NULLIF clause. It then checks the length of the field from field evaluation, which is 3, not 0.

Then SQL*Loader evaluates the DEFAULTIF clause. It compares (1:5) which is

.....

to BLANKS, which evaluates to true. Therefore, because col2 is a numeric field (integer EXTERNAL is numeric), SQL*Loader sets the final value for col2 to

0

. The row is loaded as NULL for col1 and 0 for col2.

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Loading Data Across Different Platforms

Example 6–5 DEFAULTIF Clause Specifies a Field Name

The control file specifies:

(col1 POSITION (1:5),

col2 POSITION(6:8) INTEGER EXTERNAL DEFAULTIF col1 = BLANKS)

The datafile contains:

.....123

In Example 6–5 , col1 for the row evaluates to NULL with a length of 0 (it is ....., but the trailing blanks are trimmed). col2 evaluates to 123.

When SQL*Loader determines the final value for col2, it finds no WHEN clause and no NULLIF clause. It then checks the length of the field from field evaluation, which is 3, not 0.

Then SQL*Loader evaluates the DEFAULTIF clause. As part of the evaluation, it checks to see that col1 is NULL from field evaluation. It is NULL, so the DEFAULTIF clause evaluates to false. Therefore, SQL*Loader sets the final value for col2 to

123

, its original value from field evaluation. The row is loaded as NULL for col1 and 123 for col2.

Loading Data Across Different Platforms

When a datafile created on one platform is to be loaded on a different platform, the data must be written in a form that the target system can read. For example, if the source system has a native, floating-point representation that uses 16 bytes, and the target system’s floating-point numbers are 12 bytes, the target system cannot directly read data generated on the source system.

The best solution is to load data across an Oracle Net database link, taking advantage of the automatic conversion of datatypes. This is the recommended approach, whenever feasible, and means that SQL*Loader must be run on the source system.

Problems with interplatform loads typically occur with native datatypes. In some situations, it is possible to avoid problems by lengthening a field by padding it with zeros, or to read only part of the field to shorten it (for example, when an 8-byte integer is to be read on a system that uses 4-byte integers, or the reverse). Note, however, that incompatible datatype implementation may prevent this.

If you cannot use an Oracle Net database link and the datafile must be accessed by

SQL*Loader running on the target system, it is advisable to use only the portable

SQL*Loader datatypes (for example, CHAR, DATE, VARCHARC, and numeric

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Byte Ordering

EXTERNAL

). Datafiles written using these datatypes may be longer than those written with native datatypes. They may take more time to load, but they transport more readily across platforms.

If you know in advance that the byte ordering schemes or native integer lengths differ between the platform on which the input data will be created and the platform on which SQL*loader will be run, then investigate the possible use of the appropriate technique to indicate the byte order of the data or the length of the native integer. Possible techniques for indicating the byte order are to use the

BYTEORDER

parameter or to place a byte-order mark (BOM) in the file. Both methods are described in Byte Ordering on page 6-37. It may then be possible to eliminate the incompatibilities and achieve a successful cross-platform data load. If the byte order is different from the SQL*Loader default, then you must indicate a byte order.

Byte Ordering

Note:

The information in this section is only applicable if you are planning to create input data on a system that has a different byte-ordering scheme than the system on which SQL*Loader will be run. Otherwise, you can skip this section.

SQL*Loader can load data from a datafile that was created on a system whose byte ordering is different from the byte ordering on the system where SQL*Loader is running, even if the datafile contains certain nonportable datatypes.

By default, SQL*Loader uses the byte order of the system where it is running as the byte order for all datafiles. For example, on a Sun Solaris system, SQL*Loader uses big endian byte order. On an Intel or an Intel-compatible PC, SQL*Loader uses little endian byte order.

Byte order affects the results when data is written and read an even number of bytes at a time (typically 2 bytes, 4 bytes, or 8 bytes). The following are some examples of this:

■

■

The 2-byte integer value 1 is written as 0x0001 on a big endian system and as

0x0100 on a little endian system.

The 4-byte integer 66051 is written as 0x00010203 on a big endian system and as

0x03020100 on a little endian system.

Field List Reference

6-37

Byte Ordering

Byte order also affects character data in the UTF16 character set if it is written and read as 2-byte entities. For example, the character ’a’ (0x61 in ASCII) is written as

0x0061 in UTF16 on a big endian system, but as 0x6100 on a little endian system.

All Oracle-supported character sets, except UTF16, are written one byte at a time.

So, even for multibyte character sets such as UTF8, the characters are written and read the same way on all systems, regardless of the byte order of the system.

Therefore, data in the UTF16 character set is nonportable because it is byte-order dependent. Data in all other Oracle-supported character sets is portable.

Byte order in a datafile is only an issue if the datafile that contains the byte-order-dependent data is created on a system that has a different byte order from the system on which SQL*Loader is running. If SQL*Loader knows the byte order of the data, it swaps the bytes as necessary to ensure that the data is loaded correctly in the target database. Byte swapping means that data in big endian format is converted to little endian format, or the reverse.

To indicate byte order of the data to SQL*Loader, you can use the BYTEORDER parameter, or you can place a byte-order mark (BOM) in the file. If you do not use one of these techniques, SQL*Loader will not correctly load the data into the datafile.

See Also:

Case Study 11: Loading Data in the Unicode Character

Set on page 10-47 for an example of how SQL*Loader handles byte swapping

Specifying Byte Order

To specify the byte order of data in the input datafiles, use the following syntax in the SQL*Loader control file:

ENDIAN

BYTEORDER

BIG

LITTLE

The BYTEORDER parameter has the following characteristics:

■

BYTEORDER

is placed after the LENGTH parameter in the SQL*Loader control file.

■

It is possible to specify a different byte order for different datafiles. However, the BYTEORDER specification before the INFILE parameters applies to the entire list of primary datafiles.

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Oracle9 i

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Byte Ordering

■

■

■

■

The BYTEORDER specification for the primary datafiles is also used as the default for LOBFILEs and SDFs. To override this default, specify BYTEORDER with the LOBFILE or SDF specification.

The BYTEORDER parameter is not applicable to data contained within the control file itself.

The BYTEORDER parameter applies to the following:

–

Binary INTEGER and SMALLINT data

–

Binary lengths in varying-length fields (that is, for the VARCHAR,

VARGRAPHIC

, VARRAW, and LONG VARRAW datatypes)

–

Character data for datafiles in the UTF16 character set

–

FLOAT and DOUBLE datatypes, if the system where the data was written has a compatible floating-point representation with that on the system where

SQL*Loader is running

The BYTEORDER parameter does not apply to any of the following:

–

Raw datatypes (RAW, VARRAW, or VARRAWC)

–

Graphic datatypes (GRAPHIC, VARGRAPHIC, or GRAPHIC EXTERNAL)

–

Character data for datafiles in any character set other than UTF16

–

ZONED

or (packed) DECIMAL datatypes

Using Byte Order Marks (BOMs)

Datafiles that use a Unicode encoding (UTF-16 or UTF-8) may contain a byte-order mark (BOM) in the first few bytes of the file. For a datafile that uses the character set

UTF16, the value 0xFEFF in the first two bytes of the file is the BOM indicating that the file contains big endian data. A value of 0xFFFE is the BOM indicating that the file contains little endian data.

If the first primary datafile uses the UTF16 character set and it also begins with a

BOM, that mark is read and interpreted to determine the byte order for all primary datafiles. SQL*Loader reads and interprets the BOM, skips it, and begins processing data with the byte immediately after the BOM. The BOM setting overrides any

BYTEORDER specification for the first primary datafile. BOMs in datafiles other than the first primary datafile are read and used for checking for byte-order conflicts only. They do not change the byte-order setting that SQL*Loader uses in processing the datafile.

Field List Reference

6-39

Byte Ordering

In summary, the precedence of the byte-order indicators for the first primary datafile is as follows:

■

BOM in the first primary datafile, if the datafile uses a Unicode character set that is byte-order dependent (UTF16) and a BOM is present

■

■

BYTEORDER

parameter value, if specified before the INFILE parameters

The byte order of the system where SQL*Loader is running

For a datafile that uses a UTF8 character set, a BOM of 0xEFBBBF in the first 3 bytes indicates that the file contains UTF8 data. It does not indicate the byte order of the data, because data in UTF8 is not byte-order dependent. If SQL*Loader detects a

UTF8 BOM, it skips it but does not change any byte-order settings for processing the datafiles.

SQL*Loader first establishes a byte-order setting for the first primary datafile using the precedence order just defined. This byte-order setting is used for all primary datafiles. If another primary datafile uses the character set UTF16 and also contains a BOM, the BOM value is compared to the byte-order setting established for the first primary datafile. If the BOM value matches the byte-order setting of the first primary datafile, SQL*Loader skips the BOM, and uses that byte-order setting to begin processing data with the byte immediately after the BOM. If the BOM value does not match the byte-order setting established for the first primary datafile, then

SQL*Loader issues an error message and stops processing.

If any LOBFILEs or secondary datafiles are specified in the control file, SQL*Loader establishes a byte-order setting for each LOBFILE and secondary datafile (SDF) when it is ready to process the file. The default byte-order setting for LOBFILEs and

SDFs is the byte-order setting established for the first primary datafile. This is overridden if the BYTEORDER parameter is specified with a LOBFILE or SDF. In either case, if the LOBFILE or SDF uses the UTF16 character set and contains a

BOM, the BOM value is compared to the byte-order setting for the file. If the BOM value matches the byte-order setting for the file, SQL*Loader skips the BOM, and uses that byte-order setting to begin processing data with the byte immediately after the BOM. If the BOM value does not match, then SQL*Loader issues an error message and stops processing.

In summary, the precedence of the byte-order indicators for LOBFILEs and SDFs is as follows:

■

BYTEORDER

parameter value specified with the LOBFILE or SDF

■

The byte-order setting established for the first primary datafile

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Oracle9 i

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Loading All-Blank Fields

Suppressing Checks for BOMs

A datafile in a Unicode character set may contain binary data that matches the BOM in the first bytes of the file. For example the integer(2) value 0xFEFF = 65279 decimal matches the big endian BOM in UTF16. In that case, you can tell

SQL*Loader to read the first bytes of the datafile as data and not check for a BOM by specifying the BYTEORDERMARK parameter with the value NOCHECK. The syntax for the BYTEORDERMARK parameter is:

BYTEORDERMARK

CHECK

NOCHECK

BYTEORDERMARK NOCHECK

indicates that SQL*Loader should not check for a BOM and should read all the data in the datafile as data.

BYTEORDERMARK CHECK

tells SQL*Loader to check for a BOM. This is the default behavior for a datafile in a Unicode character set. But this specification may be used in the control file for clarification. It is an error to specify BYTEORDERMARK CHECK for a datafile that uses a non-Unicode character set.

The BYTEORDERMARK parameter has the following characteristics:

■

It is placed after the optional BYTEORDER parameter in the SQL*Loader control file.

■

■

■

It applies to the syntax specification for primary datafiles, as well as to

LOBFILEs and secondary datafiles (SDFs).

It is possible to specify a different BYTEORDERMARK value for different datafiles; however, the BYTEORDERMARK specification before the INFILE parameters applies to the entire list of primary datafiles.

The BYTEORDERMARK specification for the primary datafiles is also used as the default for LOBFILEs and SDFs, except that the value CHECK is ignored in this case if the LOBFILE or SDF uses a non-Unicode character set. This default setting for LOBFILEs and secondary datafiles can be overridden by specifying

BYTEORDERMARK

with the LOBFILE or SDF specification.

Loading All-Blank Fields

Fields that are numeric or totally blank cause the record to be rejected. To load one of these fields as NULL, use the NULLIF clause with the BLANKS parameter.

Field List Reference

6-41

Trimming Whitespace

If an all-blank CHAR field is surrounded by enclosure delimiters, then the blanks within the enclosures are loaded. Otherwise, the field is loaded as NULL.

A DATE field that consists entirely of blanks is loaded as a NULL field.

See Also:

■

■

■

Case Study 6: Loading Data Using the Direct Path Load

Method on page 10-24 for an example of how to load all-blank fields as NULL with the NULLIF clause

Trimming Whitespace on page 6-42

Preserving Whitespace on page 6-49

Trimming Whitespace

Blanks, tabs, and other nonprinting characters (such as carriage returns and line feeds) constitute whitespace. Leading whitespace occurs at the beginning of a field.

Trailing whitespace occurs at the end of a field. Depending on how the field is specified, whitespace may or may not be included when the field is inserted into the database. This is illustrated in Figure 6–1 where two CHAR fields are defined for a data record.

The field specifications are contained in the control file. The control file CHAR specification is not the same as the database CHAR specification. A data field defined as CHAR in the control file merely tells SQL*Loader how to create the row insert. The data could then be inserted into a CHAR, VARCHAR2, NCHAR, NVARCHAR, or even a

NUMBER

or DATE column in the database, with the Oracle database server handling any necessary conversions.

By default, SQL*Loader removes trailing spaces from CHAR data before passing it to the database. So, in Figure 6–1 , both field 1 and field 2 are passed to the database as

3-byte fields. However, when the data is inserted into the table, there is a difference.

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Trimming Whitespace

Figure 6–1 Example of Field Conversion

DATAFILE

Field 1 Field 2 a a a b b b

CHAR (5)

Control File Specifications

CHAR (5)

ROW

INSERT

aaa bbb

SQL*Loader

DATABASE

Table

Column 1 a a a _ _

CHAR (5)

Column Datatypes

Column 2 b b b

VARCHAR (5)

SERVER

Column 1 is defined in the database as a fixed-length CHAR column of length 5. So the data (aaa) is left-justified in that column, which remains 5 bytes wide. The extra space on the right is padded with blanks. Column 2, however, is defined as a varying-length field with a maximum length of 5 bytes. The data for that column

(bbb) is left-justified as well, but the length remains 3 bytes.

Table 6–5 summarizes when and how whitespace is removed from input data fields when PRESERVE BLANKS is not specified. See Preserving Whitespace on page 6-49 for details on how to prevent whitespace trimming.

Field List Reference

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Trimming Whitespace

Table 6–5 Behavior Summary for Trimming Whitespace

Specification Data Result

Leading

Whitespace

Present

1

Trailing

Whitespace

Present

1

Predetermined size

Terminated

Enclosed

Terminated and enclosed

Optional enclosure

(present)

Optional enclosure

(absent)

__aa__

__aa__,

"__aa__"

"__aa__",

"__aa__",

__aa__,

__aa

__aa__

__aa__

__aa__

__aa__ aa__

Yes

Yes

Yes

Yes

Yes

No

No

Yes

2

Yes

Yes

Yes

Yes

Previous field terminated by whitespace

__aa__ aa

3 No

3

1

2

3

When an all-blank field is trimmed, its value is NULL.

Except for fields that are terminated by whitespace.

Presence of trailing whitespace depends on the current field’s specification, as shown by the other entries in the table

.

The rest of this section discusses the following topics with regard to trimming whitespace:

■

■

Datatypes for Which Whitespace Can Be Trimmed

Field Length Specifications for Datatypes for Which Whitespace Can Be

Trimmed

■

■

■

■

Relative Positioning of Fields

Leading Whitespace

Trailing Whitespace

Enclosed Fields

Datatypes for Which Whitespace Can Be Trimmed

The information in this section applies only to fields specified with one of the character-data datatypes:

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Oracle9 i

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Trimming Whitespace

■

■

■

CHAR

datatype

Datetime and interval datatypes

Numeric EXTERNAL datatypes:

–

INTEGER EXTERNAL

–

FLOAT EXTERNAL

–

(packed) DECIMAL EXTERNAL

–

ZONED

(decimal) EXTERNAL

Note:

Although VARCHAR and VARCHARC fields also contain character data, these fields are never trimmed. These fields include all whitespace that is part of the field in the datafile.

Field Length Specifications for Datatypes for Which Whitespace Can Be Trimmed

There are two ways to specify field length. If a field has a constant length that is defined in the control file with a position specification or the datatype and length, then it has a predetermined size. If a field’s length is not known in advance, but depends on indicators in the record, then the field is delimited, using either enclosure or termination delimiters.

If a position specification with start and end values is defined for a field that also has enclosure or termination delimiters defined, only the position specification has any effect. The enclosure and termination delimiters are ignored.

Predetermined Size Fields

Fields that have a predetermined size are specified with a starting position and ending position, or with a length, as in the following examples: loc POSITION(19:31) loc CHAR(14)

In the second case, even though the exact position of the field is not specified, the length of the field is predetermined.

Delimited Fields

Delimiters are characters that demarcate field boundaries.

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Trimming Whitespace

Enclosure delimiters surround a field, like the quotation marks in the following example, where "__" represents blanks or tabs:

"__aa__"

Termination delimiters signal the end of a field, like the comma in the following example:

__aa__,

Delimiters are specified with the control clauses TERMINATED BY and ENCLOSED

BY

, as shown in the following example: loc TERMINATED BY "." OPTIONALLY ENCLOSED BY ’|’

Relative Positioning of Fields

This section describes how SQL*Loader determines the starting position of a field in the following situations:

■

No Start Position Specified for a Field

■

■

Previous Field Terminated by a Delimiter

Previous Field Has Both Enclosure and Termination Delimiters

No Start Position Specified for a Field

When a starting position is not specified for a field, it begins immediately after the end of the previous field.

Figure 6–2 illustrates this situation when the previous field (Field 1) has a predetermined size.

Figure 6–2 Relative Positioning After a Fixed Field

Field 1 CHAR(9) Field 2 TERMINATED BY "," a a a a b b b b ,

Previous Field Terminated by a Delimiter

If the previous field (Field 1) is terminated by a delimiter, then the next field begins immediately after the delimiter, as shown in Figure 6–3 .

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Figure 6–3 Relative Positioning After a Delimited Field

Field 1 TERMINATED BY "," Field 2 TERMINATED BY "," a a a a , b b b b ,

Previous Field Has Both Enclosure and Termination Delimiters

When a field is specified with both enclosure delimiters and a termination delimiter, then the next field starts after the termination delimiter, as shown in Figure 6–4 . If a nonwhitespace character is found after the enclosure delimiter, but before the terminator, then SQL*Loader generates an error.

Figure 6–4 Relative Positioning After Enclosure Delimiters

Field 1 TERMINATED BY ","

ENCLOSED BY ' " '

Field 2 TERMINATED BY ","

" a a a a " , b b b b ,

Leading Whitespace

In Figure 6–4 , both fields are stored with leading whitespace. Fields do not include leading whitespace in the following cases:

■

When the previous field is terminated by whitespace, and no starting position is specified for the current field

■

When optional enclosure delimiters are specified for the field, and the enclosure delimiters are not present

These cases are illustrated in the following sections.

Previous Field Terminated by Whitespace

If the previous field is TERMINATED BY WHITESPACE, then all whitespace after the field acts as the delimiter. The next field starts at the next nonwhitespace character.

Figure 6–5 illustrates this case.

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Trimming Whitespace

Figure 6–5 Fields Terminated by Whitespace

Field 1 TERMINATED

BY WHITESPACE

Field 2 TERMINATED

BY WHITESPACE a a a a b b b b

This situation occurs when the previous field is explicitly specified with the

TERMINATED BY WHITESPACE clause, as shown in the example. It also occurs when you use the global FIELDS TERMINATED BY WHITESPACE clause.

Optional Enclosure Delimiters

Leading whitespace is also removed from a field when optional enclosure delimiters are specified but not present.

Whenever optional enclosure delimiters are specified, SQL*Loader scans forward, looking for the first enclosure delimiter. If an enclosure delimiter is not found,

SQL*Loader skips over whitespace, eliminating it from the field. The first nonwhitespace character signals the start of the field. This situation is shown in

Field 2 in Figure 6–6 . (In Field 1 the whitespace is included because SQL*Loader found enclosure delimiters for the field.)

Figure 6–6 Fields Terminated by Optional Enclosure Delimiters

Field 1 TERMINATED BY " , "

OPTIONALLY ENCLOSED BY ' " '

Field 2 TERMINATED BY " , "

OPTIONALLY ENCLOSED BY ' " '

" a a a a " , b b b b ,

Unlike the case when the previous field is TERMINATED BY WHITESPACE, this specification removes leading whitespace even when a starting position is specified for the current field.

Note:

If enclosure delimiters are present, leading whitespace after the initial enclosure delimiter is kept, but whitespace before this delimiter is discarded. See the first quotation mark in Field 1,

Figure 6–6 .

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Preserving Whitespace

Trailing Whitespace

Trailing whitespace is always trimmed from character-data fields that have a predetermined size. These are the only fields for which trailing whitespace is always trimmed.

Enclosed Fields

If a field is enclosed, or terminated and enclosed, like the first field shown in

Figure 6–6 , then any whitespace outside the enclosure delimiters is not part of the field. Any whitespace between the enclosure delimiters belongs to the field, whether it is leading or trailing whitespace.

Preserving Whitespace

To prevent whitespace trimming in all CHAR, DATE, and numeric EXTERNAL fields, you specify PRESERVE BLANKS in the control file. Whitespace trimming is described in Trimming Whitespace on page 6-42.

PRESERVE BLANKS Option

The PRESERVE BLANKS option:

■

Retains leading whitespace when optional enclosure delimiters are not present

■

Leaves trailing whitespace intact when fields are specified with a predetermined size

For example, consider the following field, where underscores represent blanks:

__aa__,

If this field is loaded with the following control clause, then both the leading whitespace and the trailing whitespace are retained if PRESERVE BLANKS is specified. Otherwise, the leading whitespace is trimmed.

TERMINATED BY ’,’ OPTIONALLY ENCLOSED BY ’"’

Note:

The word BLANKS is not optional. Both words must be specified.

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Applying SQL Operators to Fields

Terminated by Whitespace

When the previous field is terminated by whitespace, then PRESERVE BLANKS does not preserve the space at the beginning of the next field, unless that field is specified with a POSITION clause that includes some of the whitespace. Otherwise,

SQL*Loader scans past all whitespace at the end of the previous field until it finds a nonblank, nontab character.

Applying SQL Operators to Fields

A wide variety of SQL operators can be applied to field data with the SQL string.

This string can contain any combination of SQL expressions that are recognized by the Oracle database server as valid for the VALUES clause of an INSERT statement.

In general, any SQL function that returns a single value that is compatible with the target column’s datatype can be used. SQL strings can be applied to simple scalar column types as well as to user-defined complex types such as column object and collections. See the information about expressions in the Oracle9i SQL Reference.

The column name and the name of the column in the SQL string must match exactly, including the quotation marks, as in the following example of specifying the control file:

LOAD DATA

INFILE *

APPEND INTO TABLE XXX

( "Last" position(1:7) char "UPPER(:\"Last\")"

FIRST position(8:15) char "UPPER(:FIRST)"

)

BEGINDATA

Phil Locke

Jason Durbin

The following requirements and restrictions apply when you are using SQL strings:

■

The SQL string appears after any other specifications for a given column.

■

■

The SQL string must be enclosed in double quotation marks.

To enclose a column name in quotation marks within a SQL string, you must use escape characters.

In the preceding example, Last is enclosed in double quotation marks to preserve the mixed case, and the double quotation marks necessitate the use of the backslash (escape) character.

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■

■

■

■

■

■

■

■

■

■

If the SQL string contains a column name that references a column object attribute, then the full field name must be used and it must be enclosed in quotation marks.

The SQL string is evaluated after any NULLIF or DEFAULTIF clauses, but before a date mask.

If the Oracle database server does not recognize the string, the load terminates in error. If the string is recognized, but causes a database error, the row that caused the error is rejected.

SQL strings are required when using the EXPRESSION parameter in a field specification.

If the SQL string contains a bind variable, the bind variable cannot be longer than 4000 bytes or the record will be rejected.

The SQL string cannot reference fields that are loaded using OID, SID, REF, or

BFILE

. Also, it cannot reference filler fields.

In direct path mode, a SQL string cannot reference a VARRAY, nested table, or

LOB

column. This also includes a VARRAY, nested table, or LOB column that is an attribute of a column object.

The SQL string cannot be used on RECNUM, SEQUENCE, CONSTANT, or SYSDATE fields.

The SQL string cannot be used on LOBs, BFILEs, XML columns, or a file that is an element of a collection.

In direct path mode, the final result that is returned after evaluation of the expression in the SQL string must be a scalar datatype. That is, the expression may not return an object or collection datatype when performing a direct path load.

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Applying SQL Operators to Fields

Referencing Fields

To refer to fields in the record, precede the field name with a colon (:). Field values from the current record are substituted. A field name preceded by a colon (:) in a

SQL string is also referred to as a bind variable. The following example illustrates how a reference is made to both the current field and to other fields in the control file:

LOAD DATA

INFILE *

APPEND INTO TABLE YYY

(

field1 POSITION(1:6) CHAR "LOWER(:field1)"

field2 CHAR TERMINATED BY ’,’

NULLIF ((1) = ’a’) DEFAULTIF ((1)= ’b’)

"RTRIM(:field2)"

field3 CHAR(7) "TRANSLATE(:field3, ’:field1’, ’:1’)",

field4 COLUMN OBJECT

(

attr1 CHAR(3) "UPPER(":\"FIELD4.ATTR3\")",

attr2 CHAR(2),

attr3 CHAR(3) ":\"FIELD4.ATTR1\" + 1"

),

field5 EXPRESSION "MYFUNC(:FIELD4, SYSDATE)"

)

BEGINDATA

ABCDEF1234511 ,:field1500YYabc abcDEF67890 ,:field2600ZZghl

Note the following about the preceding example:

■

Only the :field1 that is not in single quotation marks is interpreted as a bind variable; ’:field1’ and ’:1’ are text literals that are passed unchanged to the TRANSLATE function. For more information on the use of quotation marks inside quoted strings, see Specifying Filenames and Object Names on page 5-5.

■

■

For each input record read, the value of the field referenced by the bind variable will be substituted for the bind variable. For example, the value ABCDEF in the first record is mapped to the first field :field1. This value is then passed as an argument to the LOWER function.

When a bind variable is a reference to an attribute of a column object, the full field name must be in uppercase and enclosed in quotation marks. For instance,

:\"FIELD4.ATTR1\"

and :\"FIELD4.ATTR3\".

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Applying SQL Operators to Fields

■

■

A bind variable in a SQL string need not reference the current field. In the preceding example, the bind variable in the SQL string for field FIELD4.ATTR1

references field FIELD4.ATTR3. The field FIELD4.ATTR1 is still mapped to the values 500 and 600 in the input records, but the final values stored in its corresponding columns are ABC and GHL.

field5

is not mapped to any field in the input record. The value that is stored in the target column is the result of executing the MYFUNC PL/SQL function, which takes two arguments. The use of the EXPRESSION parameter requires that a SQL string be used to compute the final value of the column because no input data is mapped to the field.

Common Uses of SQL Operators in Field Specifications

SQL operators are commonly used for the following tasks:

■

Loading external data with an implied decimal point:

field1 POSITION(1:9) DECIMAL EXTERNAL(8) ":field1/1000"

■

Truncating fields that could be too long:

field1 CHAR TERMINATED BY "," "SUBSTR(:field1, 1, 10)"

Combinations of SQL Operators

Multiple operators can also be combined, as in the following examples: field1 POSITION(*+3) INTEGER EXTERNAL

"TRUNC(RPAD(:field1,6,’0’), -2)" field1 POSITION(1:8) INTEGER EXTERNAL

"TRANSLATE(RTRIM(:field1),’N/A’, ’0’)" field1 CHAR(10)

"NVL( LTRIM(RTRIM(:field1)), ’unknown’ )"

Using SQL Strings with a Date Mask

When a SQL string is used with a date mask, the date mask is evaluated after the

SQL string. Consider a field specified as follows: field1 DATE "dd-mon-yy" "RTRIM(:field1)"

SQL*Loader internally generates and inserts the following:

TO_DATE(RTRIM(<field1_value>), ’dd-mon-yyyy’)

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Note that when using the DATE field datatype, it is not possible to have a SQL string without a date mask. This is because SQL*Loader assumes that the first quoted string it finds after the DATE parameter is a date mask. For instance, the following field specification would result in an error (ORA-01821: date format not recognized): field1 DATE "RTRIM(TO_DATE(:field1, ’dd-mon-yyyy’))"

In this case, a simple workaround is to use the CHAR datatype.

Interpreting Formatted Fields

It is possible to use the TO_CHAR operator to store formatted dates and numbers.

For example: field1 ... "TO_CHAR(:field1, ’$09999.99’)"

This example could store numeric input data in formatted form, where field1 is a character column in the database. This field would be stored with the formatting characters (dollar sign, period, and so on) already in place.

You have even more flexibility, however, if you store such values as numeric quantities or dates. You can then apply arithmetic functions to the values in the database, and still select formatted values for your reports.

The SQL string is used in Case Study 7: Extracting Data from a Formatted Report on page 10-28 to load data from a formatted report.

Using SQL*Loader to Generate Data for Input

The parameters described in this section provide the means for SQL*Loader to generate the data stored in the database record, rather than reading it from a datafile. The following parameters are described:

■

CONSTANT Parameter

■

■

■

■

EXPRESSION Parameter

RECNUM Parameter

SYSDATE Parameter

SEQUENCE Parameter

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Using SQL*Loader to Generate Data for Input

Loading Data Without Files

It is possible to use SQL*Loader to generate data by specifying only sequences, record numbers, system dates, constants, and SQL string expressions as field specifications.

SQL*Loader inserts as many records as are specified by the LOAD statement. The

SKIP

parameter is not permitted in this situation.

SQL*Loader is optimized for this case. Whenever SQL*Loader detects that only generated specifications are used, it ignores any specified datafile—no read I/O is performed.

In addition, no memory is required for a bind array. If there are any WHEN clauses in the control file, SQL*Loader assumes that data evaluation is necessary, and input records are read.

Setting a Column to a Constant Value

This is the simplest form of generated data. It does not vary during the load or between loads.

CONSTANT Parameter

To set a column to a constant value, use CONSTANT followed by a value:

CONSTANT value

CONSTANT

data is interpreted by SQL*Loader as character input. It is converted, as necessary, to the database column type.

You may enclose the value within quotation marks, and you must do so if it contains whitespace or reserved words. Be sure to specify a legal value for the target column. If the value is bad, every record is rejected.

Numeric values larger than 2^32 - 1 (4,294,967,295) must be enclosed in quotation marks.

Note:

Do not use the CONSTANT parameter to set a column to null.

To set a column to null, do not specify that column at all. Oracle automatically sets that column to null when loading the record. The combination of CONSTANT and a value is a complete column specification.

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Using SQL*Loader to Generate Data for Input

Setting a Column to an Expression Value

Use the EXPRESSION parameter after a column name to set that column to the value returned by a SQL operator or specially written PL/SQL function. The operator or function is indicated in a SQL string that follows the EXPRESSION parameter. Any arbitrary expression may be used in this context provided that any parameters required for the operator or function are correctly specified and that the result returned by the operator or function is compatible with the datatype of the column being loaded.

EXPRESSION Parameter

The combination of column name, EXPRESSION parameter, and a SQL string is a complete field specification.

column_name EXPRESSION "SQL string"

Setting a Column to the Datafile Record Number

Use the RECNUM parameter after a column name to set that column to the number of the logical record from which that record was loaded. Records are counted sequentially from the beginning of the first datafile, starting with record 1. RECNUM is incremented as each logical record is assembled. Thus it increments for records that are discarded, skipped, rejected, or loaded. If you use the option SKIP=10, the first record loaded has a RECNUM of 11.

RECNUM Parameter

The combination of column name and RECNUM is a complete column specification.

column_name RECNUM

Setting a Column to the Current Date

A column specified with SYSDATE gets the current system date, as defined by the

SQL language SYSDATE parameter. See the section on the DATE datatype in Oracle9i

SQL Reference.

SYSDATE Parameter

The combination of column name and the SYSDATE parameter is a complete column specification.

column_name SYSDATE

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The database column must be of type CHAR or DATE. If the column is of type CHAR, then the date is loaded in the form ’dd-mon-yy.’ After the load, it can be loaded only in that form. If the system date is loaded into a DATE column, then it can be loaded in a variety of forms that include the time and the date.

A new system date/time is used for each array of records inserted in a conventional path load and for each block of records loaded during a direct path load.

Setting a Column to a Unique Sequence Number

The SEQUENCE parameter ensures a unique value for a particular column.

SEQUENCE

increments for each record that is loaded or rejected. It does not increment for records that are discarded or skipped.

SEQUENCE Parameter

The combination of column name and the SEQUENCE parameter is a complete column specification.

column name SEQUENCE (

COUNT

MAX integer

, incr

)

Table 6–6 describes the parameters used for column specification.

Table 6–6 Parameters Used for Column Specification

Parameter Description

column_name

SEQUENCE

COUNT

MAX integer

The name of the column in the database to which to assign the sequence

Use the SEQUENCE parameter to specify the value for a column

The sequence starts with the number of records already in the table plus the increment

The sequence starts with the current maximum value for the column plus the increment

Specifies the specific sequence number to begin with

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Using SQL*Loader to Generate Data for Input

Table 6–6 (Cont.) Parameters Used for Column Specification

Parameter Description

incr

The value that the sequence number is to increment after a record is loaded or rejected. This is optional. The default is 1.

If a record is rejected (that is, it has a format error or causes an Oracle error), the generated sequence numbers are not reshuffled to mask this. If four rows are assigned sequence numbers 10, 12, 14, and 16 in a particular column, and the row with 12 is rejected, the three rows inserted are numbered 10, 14, and 16, not 10, 12, and 14. This allows the sequence of inserts to be preserved despite data errors.

When you correct the rejected data and reinsert it, you can manually set the columns to agree with the sequence.

Case Study 3: Loading a Delimited, Free-Format File on page 10-11 provides an example of the SEQUENCE parameter.

Generating Sequence Numbers for Multiple Tables

Because a unique sequence number is generated for each logical input record, rather than for each table insert, the same sequence number can be used when inserting data into multiple tables. This is frequently useful.

Sometimes, however, you might want to generate different sequence numbers for each INTO TABLE clause. For example, your data format might define three logical records in every input record. In that case, you can use three INTO TABLE clauses, each of which inserts a different part of the record into the same table. When you use SEQUENCE(MAX), SQL*Loader will use the maximum from each table, which can lead to inconsistencies in sequence numbers.

To generate sequence numbers for these records, you must generate unique numbers for each of the three inserts. Use the number of table-inserts per record as the sequence increment and start the sequence numbers for each insert with successive numbers.

Example: Generating Different Sequence Numbers for Each Insert

Suppose you want to load the following department names into the dept table.

Each input record contains three department names, and you want to generate the department numbers automatically.

Accounting Personnel Manufacturing

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Using SQL*Loader to Generate Data for Input

Shipping Purchasing Maintenance

...

You could use the following control file entries to generate unique department numbers:

INTO TABLE dept

(deptno SEQUENCE(1, 3),

dname POSITION(1:14) CHAR)

INTO TABLE dept

(deptno SEQUENCE(2, 3),

dname POSITION(16:29) CHAR)

INTO TABLE dept

(deptno SEQUENCE(3, 3),

dname POSITION(31:44) CHAR)

The first INTO TABLE clause generates department number 1, the second number 2, and the third number 3. They all use 3 as the sequence increment (the number of department names in each record). This control file loads Accounting as department number 1, Personnel as 2, and Manufacturing as 3.

The sequence numbers are then incremented for the next record, so Shipping loads as 4, Purchasing as 5, and so on.

Field List Reference

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Using SQL*Loader to Generate Data for Input

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7

Loading Objects, LOBs, and Collections

This chapter discusses the following topics:

■

■

Loading Column Objects

Loading Object Tables

■

■

Loading REF Columns

Loading LOBs

■

■

■

Loading Collections (Nested Tables and VARRAYs)

Dynamic Versus Static SDF Specifications

Loading a Parent Table Separately from Its Child Table

Loading Column Objects

Column objects in the control file are described in terms of their attributes. If the object type on which the column object is based is declared to be nonfinal, then the column object in the control file may be described in terms of the attributes, both derived and declared, of any subtype derived from the base object type. In the datafile, the data corresponding to each of the attributes of a column object is in a data field similar to that corresponding to a simple relational column.

Loading Objects, LOBs, and Collections

7-1

Loading Column Objects

Note:

With SQL*Loader support for complex datatypes like column-objects, the possibility arises that two identical field names could exist in the control file, one corresponding to a column, the other corresponding to a column object’s attribute. Certain clauses can refer to fields (for example, WHEN, NULLIF, DEFAULTIF, SID,

OID

, REF, BFILE, and so on), causing a naming conflict if identically named fields exist in the control file.

Therefore, if you use clauses that refer to fields, you must specify the full name. For example, if field fld1 is specified to be a

COLUMN OBJECT

and it contains field fld2, when you specify fld2

in a clause such as NULLIF, you must use the full field name fld1.fld2

.

The following sections show examples of loading column objects:

■

Loading Column Objects in Stream Record Format

■

■

■

■

■

Loading Column Objects in Variable Record Format

Loading Nested Column Objects

Loading Column Objects with a Derived Subtype

Specifying Null Values for Objects

Loading Column Objects with User-Defined Constructors

Loading Column Objects in Stream Record Format

Example 7–1 shows a case in which the data is in predetermined size fields. The newline character marks the end of a physical record. You can also mark the end of a physical record by using a custom record separator in the operating system file-processing clause (os_file_proc_clause).

Example 7–1 Loading Column Objects in Stream Record Format

Control File Contents

LOAD DATA

INFILE ’sample.dat’

INTO TABLE departments

(dept_no POSITION(01:03) CHAR,

dept_name POSITION(05:15) CHAR,

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Loading Column Objects

1

dept_mgr COLUMN OBJECT

(name POSITION(17:33) CHAR,

age POSITION(35:37) INTEGER EXTERNAL,

emp_id POSITION(40:46) INTEGER EXTERNAL) )

Datafile (sample.dat)

101 Mathematics Johny Quest 30 1024

237 Physics Albert Einstein 65 0000

Note:

1.

This type of column object specification can be applied recursively to describe nested column objects.

Loading Column Objects in Variable Record Format

Example 7–2 shows a case in which the data is in delimited fields.

Example 7–2 Loading Column Objects in Variable Record Format

Control File Contents

LOAD DATA

1

INFILE ’sample.dat’ "var 6"

INTO TABLE departments

FIELDS TERMINATED BY ’,’ OPTIONALLY ENCLOSED BY ’"’

2

(dept_no

dept_name,

dept_mgr COLUMN OBJECT

(name CHAR(30),

age INTEGER EXTERNAL(5),

emp_id INTEGER EXTERNAL(5)) )

Datafile (sample.dat)

3

000034 101,Mathematics,Johny Q.,30,1024,

000039

237,Physics,"Albert Einstein",65,0000,

Notes

1.

The "var" string includes the number of bytes in the length field at the beginning of each record (in this example, the number is 6). If no value is specified, the default is 5 bytes. The maximum size of a variable record is

2^32-1. Specifying larger values will result in an error.

Loading Objects, LOBs, and Collections

7-3

Loading Column Objects

2.

3.

Although no positional specifications are given, the general syntax remains the same (the column object’s name followed by the list of its attributes enclosed in parentheses). Also note that an omitted type specification defaults to CHAR of length 255.

The first six bytes (italicized) specify the length of the forthcoming record.

These length specifications include the newline characters, which are ignored thanks to the terminators after the emp_id field.

Loading Nested Column Objects

Example 7–3 shows a control file describing nested column objects (one column object nested in another column object).

Example 7–3 Loading Nested Column Objects

Control File Contents

LOAD DATA

INFILE `sample.dat'

INTO TABLE departments_v2

FIELDS TERMINATED BY ’,' OPTIONALLY ENCLOSED BY ’"’

(dept_no CHAR(5),

dept_name CHAR(30),

dept_mgr COLUMN OBJECT

(name CHAR(30),

age INTEGER EXTERNAL(3),

emp_id INTEGER EXTERNAL(7),

1

em_contact COLUMN OBJECT

(name CHAR(30),

phone_num CHAR(20))))

Datafile (sample.dat)

101,Mathematics,Johny Q.,30,1024,"Barbie",650-251-0010,

237,Physics,"Albert Einstein",65,0000,Wife Einstein,654-3210,

Notes

1.

This entry specifies a column object nested within a column object.

Loading Column Objects with a Derived Subtype

Example 7–4 shows a case in which a nonfinal base object type has been extended to create a new derived subtype. Although the column object in the table definition is

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Loading Column Objects declared to be of the base object type, SQL*Loader allows any subtype to be loaded into the column object, provided that the subtype is derived from the base object type.

Example 7–4 Loading Column Objects with a Subtype

Object Type Definitions

CREATE TYPE person_type AS OBJECT

(name VARCHAR(30),

ssn NUMBER(9)) not final;

CREATE TYPE employee_type UNDER person_type

(empid NUMBER(5));

CREATE TABLE personnel

(deptno NUMBER(3),

deptname VARCHAR(30),

person person_type);

Control File Contents

LOAD DATA

INFILE ’sample.dat’

INTO TABLE personnel

FIELDS TERMINATED BY ’,’ OPTIONALLY ENCLOSED BY ’"’

(deptno INTEGER EXTERNAL(3),

deptname CHAR,

1

person COLUMN OBJECT TREAT AS employee_type

(name CHAR,

ssn INTEGER EXTERNAL(9),

2

empid INTEGER EXTERNAL(5)))

Datafile (sample.dat)

101,Mathematics,Johny Q.,301189453,10249,

237,Physics,"Albert Einstein",128606590,10030,

Notes

1.

The TREAT AS clause indicates that SQL*Loader should treat the column object person

as if it were declared to be of the derived type employee_type, instead of its actual declared type, person_type.

Loading Objects, LOBs, and Collections

7-5

Loading Column Objects

2.

The empid attribute is allowed here because it is an attribute of the employee_ type

. If the TREAT AS clause had not been specified, this attribute would have resulted in an error, because it is not an attribute of the column’s declared type.

Specifying Null Values for Objects

Specifying null values for nonscalar datatypes is somewhat more complex than for scalar datatypes. An object can have a subset of its attributes be null, it can have all of its attributes be null (an attributively null object), or it can be null itself (an atomically null object).

Specifying Attribute Nulls

In fields corresponding to column objects, you can use the NULLIF clause to specify the field conditions under which a particular attribute should be initialized to NULL.

Example 7–5 demonstrates this.

Example 7–5 Specifying Attribute Nulls Using the NULLIF Clause

Control File Contents

LOAD DATA

INFILE ’sample.dat’

INTO TABLE departments

(dept_no POSITION(01:03) CHAR,

dept_name POSITION(05:15) CHAR NULLIF dept_name=BLANKS, dept_mgr COLUMN OBJECT

1

( name POSITION(17:33) CHAR NULLIF dept_mgr.name=BLANKS,

1

age POSITION(35:37) INTEGER EXTERNAL

NULLIF dept_mgr.age=BLANKS,

1

emp_id POSITION(40:46) INTEGER EXTERNAL

NULLIF dept_mgr.emp_id=BLANKS))

Datafile (sample.dat)

2

101 Johny Quest 1024

237 Physics Albert Einstein 65 0000

Notes

1.

The NULLIF clause corresponding to each attribute states the condition under which the attribute value should be NULL.

2.

The age attribute of the dept_mgr value is null. The dept_name value is also null.

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Specifying Atomic Nulls

To specify in the control file the condition under which a particular object should take a null value (atomic null), you must follow that object’s name with a NULLIF clause based on a logical combination of any of the mapped fields (for example, in

Example 7–5 , the named mapped fields would be dept_no, dept_name, name, age

, emp_id, but dept_mgr would not be a named mapped field because it does not correspond (is not mapped) to any field in the datafile).

Although the preceding is workable, it is not ideal when the condition under which an object should take the value of null is independent of any of the mapped fields. In such situations, you can use filler fields.

You can map a filler field to the field in the datafile (indicating if a particular object is atomically null or not) and use the filler field in the field condition of the NULLIF clause of the particular object. This is shown in Example 7–6 .

Example 7–6 Loading Data Using Filler Fields

Control File Contents

LOAD DATA

INFILE ’sample.dat’

INTO TABLE departments_v2

FIELDS TERMINATED BY ’,’ OPTIONALLY ENCLOSED BY ’"’

(dept_no CHAR(5),

dept_name CHAR(30),

1

is_null FILLER CHAR,

2

dept_mgr COLUMN OBJECT NULLIF is_null=BLANKS

(name CHAR(30) NULLIF dept_mgr.name=BLANKS,

age INTEGER EXTERNAL(3) NULLIF dept_mgr.age=BLANKS,

emp_id INTEGER EXTERNAL(7)

NULLIF dept_mgr.emp_id=BLANKS,

em_contact COLUMN OBJECT NULLIF is_null2=BLANKS

(name CHAR(30)

NULLIF dept_mgr.em_contact.name=BLANKS,

phone_num CHAR(20)

NULLIF dept_mgr.em_contact.phone_num=BLANKS)),

1

is_null2 FILLER CHAR)

Datafile (sample.dat)

101,Mathematics,n,Johny Q.,,1024,"Barbie",608-251-0010,,

237,Physics,,"Albert Einstein",65,0000,,650-654-3210,n,

Loading Objects, LOBs, and Collections

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Notes

1.

The filler field (datafile mapped; no corresponding column) is of type CHAR

(because it is a delimited field, the CHAR defaults to CHAR(255)). Note that the

NULLIF

clause is not applicable to the filler field itself.

2.

Gets the value of null (atomic null) if the is_null field is blank.

See Also:

Specifying Filler Fields on page 6-6

Loading Column Objects with User-Defined Constructors

The Oracle9i database server automatically supplies a default constructor for every object type. This constructor requires that all attributes of the type be specified as arguments in a call to the constructor. When a new instance of the object is created, its attributes take on the corresponding values in the argument list. This constructor is known as the attribute-value constructor. SQL*Loader uses the attribute-value constructor by default when loading column objects.

It is possible to override the attribute-value constructor by creating one or more user-defined constructors. When you create a user-defined constructor, you must supply a type body that performs the user-defined logic whenever a new instance of the object is created. A user-defined constructor may have the same argument list as the attribute-value constructor but differ in the logic that its type body implements.

When the argument list of a user-defined constructor function matches the argument list of the attribute-value constructor, there is a difference in behavior between conventional and direct path SQL*Loader. Conventional path mode results in a call to the user-defined constructor. Direct path mode results in a call to the attribute-value constructor.

Example 7–7 illustrates this difference.

Example 7–7 Loading a Column Object with a User-Defined Constructor That

Matches the Attribute-Value Constructor

Object Type Definitions

CREATE TYPE person_type AS OBJECT

(name VARCHAR(30),

ssn NUMBER(9)) not final;

CREATE TYPE employee_type UNDER person_type

(empid NUMBER(5),

-- User-defined constructor that looks like an attribute-value constructor

CONSTRUCTOR FUNCTION

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employee_type (name VARCHAR2, ssn NUMBER, empid NUMBER)

RETURN SELF AS RESULT);

CREATE TYPE BODY employee_type AS

CONSTRUCTOR FUNCTION

employee_type (name VARCHAR2, ssn NUMBER, empid NUMBER)

RETURN SELF AS RESULT AS

-- This UDC makes sure that the name attribute is in uppercase.

BEGIN

SELF.name := UPPER(name);

SELF.ssn := ssn;

SELF.empid := empid;

RETURN;

END;

CREATE TABLE personnel

(deptno NUMBER(3),

deptname VARCHAR(30),

employee employee_type);

Control File Contents

LOAD DATA

INFILE *

REPLACE

INTO TABLE personnel

FIELDS TERMINATED BY ’,’ OPTIONALLY ENCLOSED BY ’"’

(deptno INTEGER EXTERNAL(3),

deptname CHAR,

employee COLUMN OBJECT

(name CHAR,

ssn INTEGER EXTERNAL(9),

empid INTEGER EXTERNAL(5)))

BEGINDATA

1

101,Mathematics,Johny Q.,301189453,10249,

237,Physics,"Albert Einstein",128606590,10030,

Notes

1.

When this control file is run in conventional path mode, the name fields, Johny

Q.

and Albert Einstein, are both loaded in uppercase. This is because the user-defined constructor is called in this mode. In contrast, when this control file is run in direct path mode, the name fields are loaded exactly as they appear

Loading Objects, LOBs, and Collections

7-9

Loading Column Objects in the input data. This is because the attribute-value constructor is called in this mode.

It is possible to create a user-defined constructor whose argument list does not match that of the attribute-value constructor. In this case, both conventional and direct path modes will result in a call to the attribute-value constructor. Consider the definitions in Example 7–8 .

Example 7–8 Loading a Column Object with a User-Defined Constructor That Does

Not Match the Attribute-Value Constructor

Object Type Definitions

CREATE SEQUENCE employee_ids

START WITH 1000

INCREMENT BY 1;

CREATE TYPE person_type AS OBJECT

(name VARCHAR(30),

ssn NUMBER(9)) not final;

CREATE TYPE employee_type UNDER person_type

(empid NUMBER(5),

-- User-defined constructor that does not look like an attribute-value

-- constructor

CONSTRUCTOR FUNCTION

employee_type (name VARCHAR2, ssn NUMBER)

RETURN SELF AS RESULT);

CREATE TYPE BODY employee_type AS

CONSTRUCTOR FUNCTION

employee_type (name VARCHAR2, ssn NUMBER)

RETURN SELF AS RESULT AS

-- This UDC makes sure that the name attribute is in lowercase and

-- assigns the employee identifier based on a sequence.

nextid NUMBER;

stmt VARCHAR2(64);

BEGIN

stmt := ’SELECT employee_ids.nextval FROM DUAL’;

EXECUTE IMMEDIATE stmt INTO nextid;

SELF.name := LOWER(name);

SELF.ssn := ssn;

SELF.empid := nextid;

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RETURN;

END;

CREATE TABLE personnel

(deptno NUMBER(3),

deptname VARCHAR(30),

employee employee_type);

If the control file described in Example 7–7 is used with these definitions, then the name fields are loaded exactly as they appear in the input data (that is, in mixed case). This is because the attribute-value constructor is called in both conventional and direct path modes.

It is still possible to load this table using conventional path mode by explicitly making reference to the user-defined constructor in a SQL expression.

Example 7–9 shows how this can be done.

Example 7–9 Loading a Column Object with a User-Defined Constructor That Does

Not Match the Attribute-Value Constructor by Using a SQL Expression

Control File Contents

LOAD DATA

INFILE *

REPLACE

INTO TABLE personnel

FIELDS TERMINATED BY ’,’ OPTIONALLY ENCLOSED BY ’"’

(deptno INTEGER EXTERNAL(3),

deptname CHAR,

name BOUNDFILLER CHAR,

ssn BOUNDFILLER INTEGER EXTERNAL(9),

employee EXPRESSION "employee_type(:NAME, :SSN)")

BEGINDATA

1

101,Mathematics,Johny Q.,301189453,

237,Physics,"Albert Einstein",128606590,

Notes

1.

The employee column object is now loaded using a SQL expression. This expression invokes the user-defined constructor with the correct number of arguments. The name fields, Johny Q. and Albert Einstein, will both be loaded in lowercase. In addition, the employee identifiers for each row’s employee column object will have taken their values from the employee_ids sequence.

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Loading Object Tables

If the control file in Example 7–9 is used in direct path mode, the following error is reported:

SQL*Loader-951: Error calling once/load initialization

ORA-26052: Unsupported type 121 for SQL expression on column EMPLOYEE.

Loading Object Tables

The control file syntax required to load an object table is nearly identical to that used to load a typical relational table.

Example 7–10 demonstrates loading an object table with primary key object identifiers (OIDs).

Example 7–10 Loading an Object Table with Primary Key OIDs

Control File Contents

LOAD DATA

INFILE ’sample.dat’

DISCARDFILE ’sample.dsc’

BADFILE ’sample.bad’

REPLACE

INTO TABLE employees

FIELDS TERMINATED BY ’,’ OPTIONALLY ENCLOSED BY ’"’

(name CHAR(30) NULLIF name=BLANKS,

age INTEGER EXTERNAL(3) NULLIF age=BLANKS,

emp_id INTEGER EXTERNAL(5))

Datafile (sample.dat)

Johny Quest, 18, 007,

Speed Racer, 16, 000,

By looking only at the preceding control file you might not be able to determine if the table being loaded was an object table with system-generated OIDs (real OIDs), an object table with primary key OIDs, or a relational table.

You may want to load data that already contains real OIDs and to specify that instead of generating new OIDs, the existing OIDs in the datafile should be used. To do this, you would follow the INTO TABLE clause with the OID clause:

OID ( fieldname )

In this clause, fieldname is the name of one of the fields (typically a filler field) from the field specification list that is mapped to a data field that contains the real

OIDs. SQL*Loader assumes that the OIDs provided are in the correct format and

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Loading Object Tables that they preserve OID global uniqueness. Therefore, to ensure uniqueness, you should use the Oracle OID generator to generate the OIDs to be loaded.

The OID clause can only be used for system-generated OIDs, not primary key OIDs.

Example 7–11 demonstrates loading real OIDs with the row-objects.

Example 7–11 Loading OIDs

Control File Contents

LOAD DATA

INFILE ’sample.dat’

INTO TABLE employees_v2

1

OID (s_oid)

FIELDS TERMINATED BY ’,’ OPTIONALLY ENCLOSED BY ’"’

(name CHAR(30) NULLIF name=BLANKS,

age INTEGER EXTERNAL(3) NULLIF age=BLANKS,

emp_id INTEGER EXTERNAL(5),

2

s_oid FILLER CHAR(32))

Datafile (sample.dat)

3

Johny Quest, 18, 007, 21E978406D3E41FCE03400400B403BC3,

Speed Racer, 16, 000, 21E978406D4441FCE03400400B403BC3,

Notes

1.

The OID clause specifies that the s_oid loader field contains the OID. The parentheses are required.

2.

3.

If s_oid does not contain a valid hexadecimal number, the particular record is rejected.

The OID in the datafile is a character string and is interpreted as a 32-digit hexadecimal number. The 32-digit hexadecimal number is later converted into a

16-byte RAW and stored in the object table.

Loading Object Tables with a Subtype

If an object table’s row object is based on a nonfinal type, SQL*Loader allows for any derived subtype to be loaded into the object table. As previously mentioned, the syntax required to load an object table with a derived subtype is almost identical to that used for a typical relational table. However, in this case, the actual subtype to be used must be named, so that SQL*Loader can determine if it is a valid subtype for the object table. This concept is illustrated in Example 7–12 .

Loading Objects, LOBs, and Collections

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Loading Object Tables

Example 7–12 Loading an Object Table with a Subtype

Object Type Definitions

CREATE TYPE employees_type AS OBJECT

(name VARCHAR2(30),

age NUMBER(3),

emp_id NUMBER(5)) not final;

CREATE TYPE hourly_emps_type UNDER employees_type

(hours NUMBER(3));

CREATE TABLE employees_v3 of employees_type;

Control File Contents

LOAD DATA

INFILE ’sample.dat’

INTO TABLE employees_v3

1

TREAT AS hourly_emps_type

FIELDS TERMINATED BY ’,’

(name CHAR(30),

age INTEGER EXTERNAL(3),

emp_id INTEGER EXTERNAL(5),

2

hours INTEGER EXTERNAL(2))

Datafile (sample.dat)

Johny Quest, 18, 007, 32,

Speed Racer, 16, 000, 20,

Notes

1.

The TREAT AS clause indicates that SQL*Loader should treat the object table as if it were declared to be of type hourly_emps_type, instead of its actual declared type, employee_type.

2.

The hours attribute is allowed here because it is an attribute of the hourly_ emps_type

. If the TREAT AS clause had not been specified, this attribute would have resulted in an error, because it is not an attribute of the object table’s declared type.

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Loading REF Columns

Loading REF Columns

SQL*Loader can load real REF columns (REFs containing real OIDs of the referenced objects), primary key REF columns, and unscoped REF columns that allow primary keys.

Real REF Columns

SQL*Loader assumes, when loading real REF columns, that the actual OIDs from which the REF columns are to be constructed are in the datafile with the rest of the data. The description of the field corresponding to a REF column consists of the column name followed by the REF clause.

The REF clause takes as arguments the table name and an OID. Note that the arguments can be specified either as constants or dynamically (using filler fields).

See ref_spec on page A-7 for the appropriate syntax.

Example 7–13 demonstrates real REF loading.

Example 7–13 Loading Real REF Columns

Control File Contents

LOAD DATA

INFILE ‘sample.dat’

INTO TABLE departments_alt_v2

FIELDS TERMINATED BY ‘,’ OPTIONALLY ENCLOSED BY ‘”’

(dept_no CHAR(5),

dept_name CHAR(30),

1

dept_mgr REF(t_name, s_oid),

s_oid FILLER CHAR(32),

t_name FILLER CHAR(30))

Datafile (sample.dat)

22345, QuestWorld, 21E978406D3E41FCE03400400B403BC3, EMPLOYEES_V2,

23423, Geography, 21E978406D4441FCE03400400B403BC3, EMPLOYEES_V2,

Notes

1.

If the specified table does not exist, the record is rejected. The dept_mgr field itself does not map to any field in the datafile.

Loading Objects, LOBs, and Collections

7-15

Loading REF Columns

Primary Key REF Columns

To load a primary key REF column, the SQL*Loader control-file field description must provide the column name followed by a REF clause. The REF clause takes for arguments a comma-separated list of field names and constant values. The first argument is the table name, followed by arguments that specify the primary key

OID on which the REF column to be loaded is based. See ref_spec on page A-7 for the appropriate syntax.

SQL*Loader assumes that the ordering of the arguments matches the relative ordering of the columns making up the primary key OID in the referenced table.

Example 7–14 demonstrates loading primary key REF columns.

Example 7–14 Loading Primary Key REF Columns

Control File Contents

LOAD DATA

INFILE ‘sample.dat’

INTO TABLE departments_alt

FIELDS TERMINATED BY ‘,’ OPTIONALLY ENCLOSED BY ‘”’

(dept_no CHAR(5),

dept_name CHAR(30),

dept_mgr REF(CONSTANT ‘EMPLOYEES’, emp_id),

emp_id FILLER CHAR(32))

Datafile (sample.dat)

22345, QuestWorld, 007,

23423, Geography, 000,

Unscoped REF Columns That Allow Primary Keys

An unscoped REF column that allows primary keys can reference both system-generated and primary key REFs. The syntax for loading into such a REF column is the same as if you were loading into a real REF column or into a primary key REF column. See Example 7–13, "Loading Real REF Columns" and

Example 7–14, "Loading Primary Key REF Columns" .

The following restrictions apply when loading into an unscoped REF column that allows primary keys:

■

Only one type of REF can be referenced by this column during a single-table load, either system-generated or primary key, but not both. If you try to

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■ reference both types, the data row will be rejected with an error message indicating that the referenced table name is invalid.

If you are loading unscoped primary key REFs to this column, only one object table can be referenced during a single-table load. That is, if you want to load unscoped primary key REFs, some pointing to object table X and some pointing to object table Y, you would have to do one of the following:

–

perform two single-table loads

–

perform a single load using multiple INTO TABLE clauses for which the

WHEN

clause keys off some aspect of the data, such as the object table name for the unscoped primary key REF. For example:

LOAD DATA

INFILE ’data.dat’

INTO TABLE orders_apk

APPEND when CUST_TBL = "CUSTOMERS_PK" fields terminated by ","

(

order_no position(1) char,

cust_tbl FILLER char,

cust_no FILLER char,

cust REF (cust_tbl, cust_no) NULLIF order_no=’0’

)

■

■

INTO TABLE orders_apk

APPEND when CUST_TBL = "CUSTOMERS_PK2" fields terminated by ","

(

order_no position(1) char,

cust_tbl FILLER char,

cust_no FILLER char,

cust REF (cust_tbl, cust_no) NULLIF order_no=’0’

)

If you do not use either of these methods, the data row will be rejected with an error message indicating that the referenced table name is invalid.

Unscoped primary key REFs in collections are not supported by SQL*Loader.

If you are loading system-generated REFs into this REF column, any limitations described in Real REF Columns on page 7-15 also apply here.

Loading Objects, LOBs, and Collections

7-17

Loading LOBs

■

If you are loading primary key REFs into this REF column, any limitations described in Primary Key REF Columns on page 7-16 also apply here.

Note:

For an unscoped REF column that allows primary keys,

SQL*Loader takes the first valid object table parsed (either from the

REF

directive or from the data rows) and uses that object table’s

OID type to determine the REF type that can be referenced in that single-table load.

Loading LOBs

A LOB is a large object type. SQL*Loader supports the following types of LOBs:

■

■

■

BLOB

: an internal LOB containing unstructured binary data

CLOB

: an internal LOB containing character data

NCLOB

: an internal LOB containing characters from a national character set

■

BFILE

: a BLOB stored outside of the database tablespaces in a server-side operating system file

LOBs can be column datatypes, and with the exception of the NCLOB, they can be an object’s attribute datatypes. LOBs can have an actual value, they can be null, or they can be "empty."

XML

columns are columns declared to be of type SYS.XMLTYPE. SQL*Loader treats

XML

columns as if they were CLOBs. All of the methods described in the following sections for loading LOB data from the primary datafile or from LOBFILEs are applicable to loading XML columns.

Note:

You cannot specify a SQL string for LOB fields. This is true even if you specify LOBFILE_spec.

Because LOBs can be quite large, SQL*Loader is able to load LOB data from either a primary datafile (in line with the rest of the data) or from LOBFILEs. This section addresses the following topics:

■

Loading LOB Data from a Primary Datafile

■

■

Loading LOB Data from an External LOBFILE (BFILE)

Loading LOB Data from LOBFILEs

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Loading LOB Data from a Primary Datafile

To load internal LOBs (BLOBs, CLOBs, and NCLOBs) or XML columns from a primary datafile, you can use the following standard SQL*Loader formats:

■

Predetermined size fields

■

■

Delimited fields

Length-value pair fields

Each of these formats is described in the following sections.

LOB Data in Predetermined Size Fields

This is a very fast and conceptually simple format in which to load LOBs, as shown in Example 7–15 .

Note:

Because the LOBs you are loading may not be of equal size, you can use whitespace to pad the LOB data to make the LOBs all of equal length within a particular data field.

To load LOBs using this format, you should use either CHAR or RAW as the loading datatype.

Example 7–15 Loading LOB Data in Predetermined Size Fields

Control File Contents

LOAD DATA

INFILE ’sample.dat’ "fix 501"

INTO TABLE person_table

(name POSITION(01:21) CHAR,

1

"RESUME" POSITION(23:500) CHAR DEFAULTIF "RESUME"=BLANKS)

Datafile (sample.dat)

Johny Quest Johny Quest

500 Oracle Parkway

[email protected] ...

Notes

1.

If the data field containing the resume is empty, the result is an empty LOB rather than a null LOB. The opposite would occur if the NULLIF clause were

Loading Objects, LOBs, and Collections

7-19

Loading LOBs used instead of the DEFAULTIF clause. You can use SQL*Loader datatypes other than CHAR to load LOBs. For example, when loading BLOBs, you would probably want to use the RAW datatype.

LOB Data in Delimited Fields

This format handles LOBs of different sizes within the same column (datafile field) without a problem. However, this added flexibility can affect performance, because

SQL*Loader must scan through the data, looking for the delimiter string.

As with single-character delimiters, when you specify string delimiters, you should consider the character set of the datafile. When the character set of the datafile is different than that of the control file, you can specify the delimiters in hexadecimal notation (that is, X’hexadecimal string’). If the delimiters are specified in hexadecimal notation, the specification must consist of characters that are valid in the character set of the input datafile. In contrast, if hexadecimal notation is not used, the delimiter specification is considered to be in the client’s (that is, the control file’s) character set. In this case, the delimiter is converted into the datafile's character set before SQL*Loader searches for the delimiter in the datafile.

Note the following:

■

■

Stutter syntax is supported with string delimiters (that is, the closing enclosure delimiter can be stuttered).

Leading whitespaces in the initial multicharacter enclosure delimiter are not allowed.

■

If a field is terminated by WHITESPACE, the leading whitespaces are trimmed.

Example 7–16 shows an example of loading LOB data in delimited fields.

Example 7–16 Loading LOB Data in Delimited Fields

Control File Contents

LOAD DATA

INFILE ’sample.dat’ "str ’|’"

INTO TABLE person_table

FIELDS TERMINATED BY ’,’

(name CHAR(25),

1

"RESUME" CHAR(507) ENCLOSED BY ’<startlob>’ AND ’<endlob>’)

Datafile (sample.dat)

Johny Quest,<startlob> Johny Quest

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Loading LOBs

500 Oracle Parkway

[email protected] ... <endlob>

2

|Speed Racer, .......

Notes

1.

<startlob>

and <endlob> are the enclosure strings. With the default byte-length semantics, the maximum length for a LOB that can be read using

CHAR(507)

is 507 bytes. If character-length semantics were used, the maximum would be 507 characters. See Character-Length Semantics on page 5-22.

2.

If the record separator ’|’ had been placed right after <endlob> and followed with the newline character, the newline would have been interpreted as part of the next record. An alternative would be to make the newline part of the record separator (for example, ’|\n’ or, in hexadecimal notation, X’7C0A’).

LOB Data in Length-Value Pair Fields

You can use VARCHAR, VARCHARC, or VARRAW datatypes to load LOB data organized in length-value pair fields. This method of loading provides better performance than using delimited fields, but can reduce flexibility (for example, you must know the LOB length for each LOB before loading).

Example 7–17 demonstrates loading LOB data in length-value pair fields.

Example 7–17 Loading LOB Data in Length-Value Pair Fields

Control File Contents

LOAD DATA

1

INFILE ’sample.dat’ "str ’<endrec>\n’"

INTO TABLE person_table

FIELDS TERMINATED BY ’,’

(name CHAR(25),

2

"RESUME" VARCHARC(3,500))

Datafile (sample.dat)

Johny Quest,479 Johny Quest

500 Oracle Parkway

[email protected]

... <endrec>

3

Speed Racer,000<endrec>

Loading Objects, LOBs, and Collections

7-21

Loading LOBs

Notes

1.

If the backslash escape character is not supported, the string used as a record separator in the example could be expressed in hexadecimal notation.

2.

"RESUME"

is a field that corresponds to a CLOB column. In the control file, it is a

VARCHARC

, whose length field is 3 bytes long and whose maximum size is 500 bytes (with byte-length semantics). If character-length semantics were used, the length would be 3 characters and the maximum size would be 500 characters.

See Character-Length Semantics on page 5-22.

3.

The length subfield of the VARCHARC is 0 (the value subfield is empty).

Consequently, the LOB instance is initialized to empty.

Loading LOB Data from an External LOBFILE (BFILE)

The BFILE datatype stores unstructured binary data in operating system files outside the database. A BFILE column or attribute stores a file locator that points to the external file containing the data. The file to be loaded as a BFILE does not have to exist at the time of loading; it can be created later. SQL*Loader assumes that the necessary directory objects have already been created (a logical alias name for a physical directory on the server's file system). For more information, see the Oracle9i

Application Developer’s Guide - Large Objects (LOBs).

A control file field corresponding to a BFILE column consists of a column name followed by the BFILE clause. The BFILE clause takes as arguments a DIRECTORY

OBJECT (the server_directory alias) name followed by a BFILE name. Both arguments can be provided as string constants, or they can be dynamically loaded through some other field. See the Oracle9i SQL Reference for more information.

In the next two examples of loading BFILEs, Example 7–18 has only the filename specified dynamically, while Example 7–19 demonstrates specifying both the BFILE and the DIRECTORY OBJECT dynamically.

Example 7–18 Loading Data Using BFILEs: Only Filename Specified Dynamically

Control File Contents

LOAD DATA

INFILE sample.dat

INTO TABLE planets

FIELDS TERMINATED BY ’,’

(pl_id CHAR(3),

pl_name CHAR(20),

fname FILLER CHAR(30),

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1

pl_pict BFILE(CONSTANT "scott_dir1", fname))

Datafile (sample.dat)

1,Mercury,mercury.jpeg,

2,Venus,venus.jpeg,

3,Earth,earth.jpeg,

Notes

1.

The directory name is quoted; therefore, the string is used as is and is not capitalized.

Example 7–19 Loading Data Using BFILEs: Filename and Directory Name Specified

Dynamically

Control File Contents

LOAD DATA

INFILE sample.dat

INTO TABLE planets

FIELDS TERMINATED BY ’,’ OPTIONALLY ENCLOSED BY ’"’

(pl_id NUMBER(4),

pl_name CHAR(20),

fname FILLER CHAR(30),

1

dname FILLER CHAR(20),

pl_pict BFILE(dname, fname) )

Datafile (sample.dat)

1, Mercury, mercury.jpeg, scott_dir1,

2, Venus, venus.jpeg, scott_dir1,

3, Earth, earth.jpeg, scott_dir2,

Notes

1.

dname

is mapped to the datafile field containing the directory name corresponding to the file being loaded.

Loading LOB Data from LOBFILEs

LOB data can be lengthy enough so that it makes sense to load it from a LOBFILE instead of from a primary datafile. In LOBFILEs, LOB data instances are still considered to be in fields (predetermined size, delimited, length-value), but these fields are not organized into records (the concept of a record does not exist within

Loading Objects, LOBs, and Collections

7-23

Loading LOBs

LOBFILEs). Therefore, the processing overhead of dealing with records is avoided.

This type of organization of data is ideal for LOB loading.

There is no requirement that a LOB from a LOBFILE fit in memory. SQL*Loader reads LOBFILEs in 64 KB chunks.

In LOBFILEs the data can be in any of the following types of fields:

■

A single LOB field into which the entire contents of a file can be read

■

■

Predetermined size fields (fixed-length fields)

Delimited fields (that is, TERMINATED BY or ENCLOSED BY)

■

The clause PRESERVE BLANKS is not applicable to fields read from a LOBFILE.

Length-value pair fields (variable-length fields)—to load data from this type of field, use the VARRAW, VARCHAR, or VARCHARC SQL*Loader datatypes

See Examples of Loading LOB Data from LOBFILEs on page 7-24 for examples of using each of these field types. All of the previously mentioned field types can be used to load XML columns.

See lobfile_spec on page A-8 for LOBFILE syntax.

Dynamic Versus Static LOBFILE Specifications

You can specify LOBFILEs either statically (the name of the file is specified in the control file) or dynamically (a FILLER field is used as the source of the filename). In either case, if the LOBFILE is not terminated by EOF, then when the end of the

LOBFILE is reached, the file is closed and further attempts to read data from that file produce results equivalent to reading data from an empty field.

However, if you have a LOBFILE that is terminated by EOF, then the entire file is always returned on each attempt to read data from that file.

You should not specify the same LOBFILE as the source of two different fields. If you do so, typically, the two fields will read the data independently.

Examples of Loading LOB Data from LOBFILEs

This section contains examples of loading data from different types of fields in

LOBFILEs.

One LOB per File

In Example 7–20 , each LOBFILE is the source of a single LOB. To load LOB data that is organized in this way, you follow the column or field name with the LOBFILE datatype specifications.

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Example 7–20 Loading LOB DATA with One LOB per LOBFILE

Control File Contents

LOAD DATA

INFILE ’sample.dat’

INTO TABLE person_table

FIELDS TERMINATED BY ’,’

(name CHAR(20),

1

ext_fname FILLER CHAR(40),

2

"RESUME" LOBFILE(ext_fname) TERMINATED BY EOF)

Datafile (sample.dat)

Johny Quest,jqresume.txt,

Speed Racer,’/private/sracer/srresume.txt’,

Secondary Datafile (jqresume.txt)

Johny Quest

500 Oracle Parkway

...

Secondary Datafile (srresume.txt)

Speed Racer

400 Oracle Parkway

...

Notes

1.

The filler field is mapped to the 40-byte data field, which is read using the

SQL*Loader CHAR datatype. This assumes the use of default byte-length semantics. If character-length semantics were used, the field would be mapped to a 40-character data field.

2.

SQL*Loader gets the LOBFILE name from the ext_fname filler field. It then loads the data from the LOBFILE (using the CHAR datatype) from the first byte to the EOF character. If no existing LOBFILE is specified, the "RESUME" field is initialized to empty.

Predetermined Size LOBs

In Example 7–21 , you specify the size of the LOBs to be loaded into a particular column in the control file. During the load, SQL*Loader assumes that any LOB data loaded into that particular column is of the specified size. The predetermined size of the fields allows the data-parser to perform optimally. However, it is often difficult to guarantee that all LOBs are the same size.

Loading Objects, LOBs, and Collections

7-25

Loading LOBs

Example 7–21 Loading LOB Data Using Predetermined Size LOBs

Control File Contents

LOAD DATA

INFILE ’sample.dat’

INTO TABLE person_table

FIELDS TERMINATED BY ’,’

(name CHAR(20),

1

"RESUME" LOBFILE(CONSTANT ’/usr/private/jquest/jqresume.txt’)

CHAR(2000))

Datafile (sample.dat)

Johny Quest,

Speed Racer,

Secondary Datafile (jqresume.txt)

Johny Quest

500 Oracle Parkway

...

Speed Racer

400 Oracle Parkway

...

Notes

1.

This entry specifies that SQL*Loader load 2000 bytes of data from the jqresume.txt

LOBFILE, using the CHAR datatype, starting with the byte following the byte loaded last during the current loading session. This assumes the use of the default byte-length semantics. If character-length semantics were used, SQL*Loader would load 2000 characters of data, starting from the first character after the last-loaded character. See Character-Length Semantics on page 5-22.

Delimited LOBs

In Example 7–22 , the LOB data instances in the LOBFILE are delimited. In this format, loading different size LOBs into the same column is not a problem. However, this added flexibility can affect performance, because

SQL*Loader must scan through the data, looking for the delimiter string.

Example 7–22 Loading LOB Data Using Delimited LOBs

Control File Contents

LOAD DATA

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INFILE ’sample.dat’

INTO TABLE person_table

FIELDS TERMINATED BY ’,’

(name CHAR(20),

1

"RESUME" LOBFILE( CONSTANT ’jqresume’) CHAR(2000)

TERMINATED BY "<endlob>\n")

Datafile (sample.dat)

Johny Quest,

Speed Racer,

Secondary Datafile (jqresume.txt)

Johny Quest

500 Oracle Parkway

... <endlob>

Speed Racer

400 Oracle Parkway

... <endlob>

Notes

1.

Because a maximum length of 2000 is specified for CHAR, SQL*Loader knows what to expect as the maximum length of the field, which can result in memory usage optimization. If you choose to specify a maximum length, you should be sure

not to underestimate its value. The TERMINATED BY clause specifies the string that terminates the LOBs. Alternatively, you could use the ENCLOSED BY clause. The

ENCLOSED BY

clause allows a bit more flexibility as to the relative positioning of the LOBs in the LOBFILE (the LOBs in the LOBFILE need not be sequential).

Length-Value Pair Specified LOBs

In Example 7–23 each LOB in the LOBFILE is preceded by its length. You could use VARCHAR, VARCHARC, or VARRAW datatypes to load LOB data organized in this way.

This method of loading can provide better performance over delimited LOBs, but at the expense of some flexibility (for example, you must know the LOB length for each LOB before loading).

Example 7–23 Loading LOB Data Using Length-Value Pair Specified LOBs

Control File Contents

LOAD DATA

INFILE ’sample.dat’

Loading Objects, LOBs, and Collections

7-27

Loading LOBs

INTO TABLE person_table

FIELDS TERMINATED BY ’,’

(name CHAR(20),

1

"RESUME" LOBFILE(CONSTANT ’jqresume’) VARCHARC(4,2000))

Datafile (sample.dat)

Johny Quest,

Speed Racer,

Secondary Datafile (jqresume.txt)

2

0501Johny Quest

500 Oracle Parkway

...

3

0000

Notes

1.

The entry VARCHARC(4,2000) tells SQL*Loader that the LOBs in the LOBFILE are in length-value pair format and that the first 4 bytes should be interpreted as the length. The value of 2000 tells SQL*Loader that the maximum size of the field is 2000 bytes. This assumes the use of the default byte-length semantics. If character-length semantics were used, the first 4 characters would be interpreted as the length in characters. The maximum size of the field would be

2000 characters. See Character-Length Semantics on page 5-22.

2.

3.

The entry 0501 preceding Johny Quest tells SQL*Loader that the LOB consists of the next 501 characters.

This entry specifies an empty (not null) LOB.

■

■

■

Considerations When Loading LOBs from LOBFILEs

Keep in mind the following when you load data using LOBFILEs:

Only LOBs and XML columns can be loaded from LOBFILEs.

The failure to load a particular LOB does not result in the rejection of the record containing that LOB. Instead, you will have a record that contains an empty

LOB. In the case of an XML column, a null value will be inserted if there is a failure loading the LOB.

It is not necessary to specify the maximum length of a field corresponding to a

LOB

type column; nevertheless, if a maximum length is specified, SQL*Loader uses it as a hint to optimize memory usage. Therefore, it is important that the maximum length specification does not understate the true maximum length.

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Loading Collections (Nested Tables and VARRAYs)

■

■

■

■

■

You cannot supply a position specification (pos_spec) when loading data from a LOBFILE.

NULLIF

or DEFAULTIF field conditions cannot be based on fields read from

LOBFILEs.

If a nonexistent LOBFILE is specified as a data source for a particular field, that field is initialized to empty. If the concept of empty does not apply to the particular field type, the field is initialized to null.

Table-level delimiters are not inherited by fields that are read from a LOBFILE.

When loading an XML column or referencing a LOB column in a SQL expression in conventional path mode, SQL*Loader must process the LOB data as a temporary LOB. To ensure the best load performance possible in these cases, refer to the guidelines concerning temporary LOB performance in Oracle9i

Application Developer’s Guide - Large Objects (LOBs).

Loading Collections (Nested Tables and VARRAYs)

Like LOBs, collections can be loaded either from a primary datafile (data inline) or from secondary datafiles (data out of line). See Secondary Datafiles (SDFs) on page 7-31 for details about SDFs.

When you load collection data, a mechanism must exist by which SQL*Loader can tell when the data belonging to a particular collection instance has ended. You can achieve this in two ways:

■

■

To specify the number of rows or elements that are to be loaded into each nested table or VARRAY instance, use the DDL COUNT function. The value specified for COUNT must either be a number or a character string containing a number, and it must be previously described in the control file before the

COUNT

clause itself. This positional dependency is specific to the COUNT clause.

COUNT(0) or COUNT(cnt_field), where cnt_field is 0 for the current row, results in a empty collection (not null), unless overridden by a NULLIF clause.

See count_spec on page A-12.

Use the TERMINATED BY and ENCLOSED BY clauses to specify a unique collection delimiter. This method cannot be used if an SDF clause is used.

In the control file, collections are described similarly to column objects. See Loading

Column Objects on page 7-1. There are some differences:

■

Collection descriptions employ the two mechanisms discussed in the preceding list.

Loading Objects, LOBs, and Collections

7-29

Loading Collections (Nested Tables and VARRAYs)

■

■

■

■

Collection descriptions can include a secondary datafile (SDF) specification.

A NULLIF or DEFAULTIF clause cannot refer to a field in an SDF unless the clause is on a field in the same SDF.

Clauses that take field names as arguments cannot use a field name that is in a collection unless the DDL specification is for a field in the same collection.

The field list must contain only one nonfiller field and any number of filler fields. If the VARRAY is a VARRAY of column objects, then the attributes of each column object will be in a nested field list.

Restrictions in Nested Tables and VARRAYs

The following restrictions exist for nested tables and VARRAYs:

■

■

■

A field_list cannot contain a collection_fld_spec.

A col_obj_spec nested within a VARRAY cannot contain a collection_ fld_spec

.

The column_name specified as part of the field_list must be the same as the column_name preceding the VARRAY parameter.

Example 7–24 demonstrates loading a VARRAY and a nested table.

Example 7–24 Loading a VARRAY and a Nested Table

Control File Contents

LOAD DATA

INFILE ‘sample.dat’ “str ‘\n’ ”

INTO TABLE dept

REPLACE

FIELDS TERMINATED BY ‘,’ OPTIONALLY ENCLOSED BY ‘”’

(

dept_no CHAR(3),

dname CHAR(25) NULLIF dname=BLANKS,

1

emps VARRAY TERMINATED BY ':'

(

emps COLUMN OBJECT

(

name CHAR(30),

age INTEGER EXTERNAL(3),

2

emp_id CHAR(7) NULLIF emps.emps.emp_id=BLANKS

)

),

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Loading Collections (Nested Tables and VARRAYs)

3

proj_cnt FILLER CHAR(3),

4

projects NESTED TABLE SDF (CONSTANT "pr.txt" "fix 57") COUNT (proj_cnt)

(

projects COLUMN OBJECT

(

project_id POSITION (1:5) INTEGER EXTERNAL(5),

project_name POSITION (7:30) CHAR

NULLIF projects.projects.project_name = BLANKS

)

)

)

Datafile (sample.dat)

101,MATH,"Napier",28,2828,"Euclid", 123,9999:0

210,"Topological Transforms",:2

Secondary Datafile (SDF) (pr.txt)

21034 Topological Transforms

77777 Impossible Proof

Notes

1.

The TERMINATED BY clause specifies the VARRAY instance terminator (note that no COUNT clause is used).

2.

Full name field references (using dot notation) resolve the field name conflict created by the presence of this filler field.

3.

4.

proj_cnt

is a filler field used as an argument to the COUNT clause.

This entry specifies the following:

–

An SDF called pr.txt as the source of data. It also specifies a fixed-record format within the SDF.

–

If COUNT is 0, then the collection is initialized to empty. Another way to initialize a collection to empty is to use a DEFAULTIF clause. The main field name corresponding to the nested table field description is the same as the field name of its nested nonfiller-field, specifically, the name of the column object field description.

Secondary Datafiles (SDFs)

Secondary datafiles (SDFs) are similar in concept to primary datafiles. Like primary datafiles, SDFs are a collection of records, and each record is made up of fields. The

Loading Objects, LOBs, and Collections

7-31

Loading Collections (Nested Tables and VARRAYs)

SDFs are specified on a per control-file-field basis. They are useful when you load large nested tables and VARRAYs.

Note:

Only a collection_fld_spec can name an SDF as its data source.

SDFs are specified using the SDF parameter. The SDF parameter can be followed by either the file specification string, or a FILLER field that is mapped to a data field containing one or more file specification strings.

As for a primary datafile, the following can be specified for each SDF:

■

■

■

The record format (fixed, stream, or variable). Also, if stream record format is used, you can specify the record separator.

The record size.

The character set for an SDF can be specified using the CHARACTERSET clause

(see Handling Different Character Encoding Schemes on page 5-16).

■

A default delimiter (using the delimiter specification) for the fields that inherit a particular SDF specification (all member fields or attributes of the collection that contain the SDF specification, with exception of the fields containing their own

LOBFILE specification).

Also note the following with regard to SDFs:

■

■

■

If a nonexistent SDF is specified as a data source for a particular field, that field is initialized to empty. If the concept of empty does not apply to the particular field type, the field is initialized to null.

Table-level delimiters are not inherited by fields that are read from an SDF.

To load SDFs larger than 64 KB, you must use the READSIZE parameter to specify a larger physical record size. You can specify the READSIZE parameter either from the command line or as part of an OPTIONS clause.

See Also:

■

■

■

READSIZE (read buffer size) on page 4-10

OPTIONS Clause on page 5-4 sdf_spec on page A-11

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Dynamic Versus Static SDF Specifications

You can specify SDFs either statically (you specify the actual name of the file) or dynamically (you use a FILLER field as the source of the filename). In either case, when the EOF of an SDF is reached, the file is closed and further attempts at reading data from that particular file produce results equivalent to reading data from an empty field.

In a dynamic secondary file specification, this behavior is slightly different.

Whenever the specification changes to reference a new file, the old file is closed, and the data is read from the beginning of the newly referenced file.

The dynamic switching of the data source files has a resetting effect. For example, when SQL*Loader switches from the current file to a previously opened file, the previously opened file is reopened, and the data is read from the beginning of the file.

You should not specify the same SDF as the source of two different fields. If you do so, typically, the two fields will read the data independently.

Loading a Parent Table Separately from Its Child Table

When you load a table that contains a nested table column, it may be possible to load the parent table separately from the child table. You can load the parent and child tables independently if the SIDs (system-generated or user-defined) are already known at the time of the load (that is, the SIDs are in the datafile with the data).

Example 7–25 and Example 7–26 illustrate how to load parent and child tables with user-provided SIDs.

Example 7–25 Loading a Parent Table with User-Provided SIDs

Control File Contents

LOAD DATA

INFILE ‘sample.dat’ “str ‘|\n’ ”

INTO TABLE dept

FIELDS TERMINATED BY ‘,’ OPTIONALLY ENCLOSED BY ‘”’

TRAILING NULLCOLS

( dept_no CHAR(3),

dname CHAR(20) NULLIF dname=BLANKS ,

mysid FILLER CHAR(32),

1

projects SID(mysid))

Loading Objects, LOBs, and Collections

7-33

Loading a Parent Table Separately from Its Child Table

Datafile (sample.dat)

101,Math,21E978407D4441FCE03400400B403BC3,|

210,”Topology”,21E978408D4441FCE03400400B403BC3,|

Notes

1.

mysid

is a filler field that is mapped to a datafile field containing the actual set-ids and is supplied as an argument to the SID clause.

Example 7–26 Loading a Child Table (the Nested Table Storage Table) with

User-Provided SIDs

Control File Contents

LOAD DATA

INFILE ‘sample.dat’

INTO TABLE dept

FIELDS TERMINATED BY ‘,’ OPTIONALLY ENCLOSED BY ‘"’

TRAILING NULLCOLS

1

SID(sidsrc)

(project_id INTEGER EXTERNAL(5),

project_name CHAR(20) NULLIF project_name=BLANKS,

sidsrc FILLER CHAR(32))

Datafile (sample.dat)

21034, "Topological Transforms", 21E978407D4441FCE03400400B403BC3,

77777, "Impossible Proof", 21E978408D4441FCE03400400B403BC3,

Notes

1.

The table-level SID clause tells SQL*Loader that it is loading the storage table for nested tables. sidsrc is the filler field name that is the source of the real set-ids.

Memory Issues When Loading VARRAY Columns

The following list describes some issues to keep in mind when you load VARRAY columns:

■

VARRAY s are created in the client’s memory before they are loaded into the database. Each element of a VARRAY requires 4 bytes of client memory before it can be loaded into the database. Therefore, when you load a VARRAY with a thousand elements, you will require at least 4000 bytes of client memory for each VARRAY instance before you can load the VARRAYs into the database. In

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■

■ many cases, SQL*Loader requires two to three times that amount of memory to successfully construct and load a VARRAY.

The BINDSIZE parameter specifies the amount of memory allocated by

SQL*Loader for loading records. Given the value specified for BINDSIZE,

SQL*Loader takes into consideration the size of each field being loaded, and determines the number of rows it can load in one transaction. The larger the number of rows, the fewer transactions, resulting in better performance.

But if the amount of memory on your system is limited, then at the expense of performance, you can specify a lower value for ROWS than SQL*Loader calculated.

Loading very large VARRAYs or a large number of smaller VARRAYs could cause you to run out of memory during the load. If this happens, specify a smaller value for BINDSIZE or ROWS and retry the load.

Loading Objects, LOBs, and Collections

7-35

Loading a Parent Table Separately from Its Child Table

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8

SQL*Loader Log File Reference

When SQL*Loader begins execution, it creates a log file. The log file contains a detailed summary of the load.

Most of the log file entries are records of successful SQL*Loader execution.

However, errors can also cause log file entries. For example, errors found during parsing of the control file appear in the log file.

This chapter describes the following sections of a SQL*Loader log file:

■

■

■

■

■

■

■

■

Header Information

Global Information

Table Information

Datafile Information

Table Load Information

Summary Statistics

Additional Summary Statistics for Direct Path Loads and Multithreading

Log File Created When EXTERNAL_TABLE=GENERATE_ONLY

Header Information

The Header Section contains the following entries:

■

■

Date of the run

Software version number

For example:

SQL*Loader: Release 9.2.0.1.0 - Production on Wed Feb 27 11:07:28 2002

SQL*Loader Log File Reference

8-1

Global Information

(c) Copyright 2002 Oracle Corporation. All rights reserved.

Global Information

The Global Information Section contains the following entries:

■

■

■

Names of all input/output files

Echo of command-line arguments

Continuation character specification

If the data is in the control file, then the datafile is shown as "*".

For example:

Control File: LOAD.CTL

Data File: LOAD.DAT

Bad File: LOAD.BAD

Discard File: LOAD.DSC

(Allow all discards)

Number to load: ALL

Number to skip: 0

Errors allowed: 50

Bind array: 64 rows, maximum of 65536 bytes

Continuation: 1:1 = ’*’, in current physical record

Path used: Conventional

Table Information

The Table Information Section provides the following entries for each table loaded:

■

■

■

■

Table name

Load conditions, if any. That is, whether all records were loaded or only those meeting criteria specified in the WHEN clause.

INSERT

, APPEND, or REPLACE specification

The following column information:

–

Column name

–

If found in a datafile, the position, length, delimiter, and datatype. See

Column Information on page 8-3 for a description of these columns.

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Oracle9 i

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Table Information

–

If specified, RECNUM, SEQUENCE, CONSTANT, or EXPRESSION

–

If specified, DEFAULTIF or NULLIF

For example:

Table EMP, loaded from every logical record.

Insert option in effect for this table: REPLACE

Column Name Position Len Term Encl Datatype

-------------------------------------- --- ---- ---- ---------

empno 1:4 4 CHARACTER

ename 6:15 10 CHARACTER

job 17:25 9 CHARACTER

mgr 27:30 4 CHARACTER

sal 32:39 8 CHARACTER

comm 41:48 8 CHARACTER

deptno 50:51 2 CHARACTER

Column empno is NULL if empno = BLANKS

Column mgr is NULL if mgr = BLANKS

Column sal is NULL if sal = BLANKS

Column comm is NULL if comm = BLANKS

Column deptno is NULL if deptno = BLANKS

Column Information

This section contains a more detailed description of the column information that is provided in the Table Information Section of the SQL*Loader log file.

■

■

■

■

■

Position

The following are the possibilities for the Position column:

If a position is specified, the position values are in bytes, starting with byte position 1, regardless of whether byte-length semantics or character-length semantics are used.

If both a start and end position are specified, they are separated by a colon.

If only a start position is specified, then only that position is displayed.

If no start or end position is specified, then FIRST is displayed for the first field and NEXT is displayed for other fields.

If the start position is derived from other information, then DERIVED is displayed.

SQL*Loader Log File Reference

8-3

Datafile Information

Length

The length, in bytes, is displayed under the heading Len. It gives the maximum size of the field, including the size of any embedded length fields. The size will be different with byte-length semantics versus character-length semantics. For example, for VARCHAR (2,10) with byte-length semantics, the length is 2 (the size of the length field) plus 10 (maximum size of the field itself), which equals 12 bytes.

For VARCHAR (2,10) with character-length semantics, the length is calculated using the maximum size, in bytes, of a character in the datafile character set.

For fields that do not have a specified maximum length, an asterisk (*) is written in the Length column.

Delimiter

The delimiters are displayed under the headings, Term (for terminated by) and

Encl

(for enclosed by). If the delimiter is optional, it is preceded by O and is displayed within parentheses.

Datatype

The datatype is displayed as specified in the control file.

If the SQL*Loader control file contains any directives for loading datetime and interval datatypes, then the log file contains the parameter DATE, DATETIME, or

INTERVAL

under the Datatype heading. If applicable, the parameter DATE,

DATETIME,

or INTERVAL is followed by the corresponding mask. For example:

Table emp, loaded from every logical record.

Insert option in effect for this table: REPLACE

Column Name Position Len Term Encl Datatype

-------------------------------------- --- ---- ---- ---------

col1 NEXT * DATETIME HH.MI.SSXFF AM

Datafile Information

The Datafile Information Section appears only for datafiles with data errors, and provides the following entries:

■

■

SQL*Loader and Oracle data record errors

Records discarded

For example:

Record 2: Rejected - Error on table EMP.

8-4

Oracle9 i

Database Utilities

Summary Statistics

ORA-00001: unique constraint < name > violated

Record 8: Rejected - Error on table emp, column deptno.

ORA-01722: invalid number

Record 3: Rejected - Error on table proj, column projno.

ORA-01722: invalid number

Table Load Information

The Table Load Information Section provides the following entries for each table that was loaded:

■

■

■

Number of rows loaded

Number of rows that qualified for loading but were rejected due to data errors

Number of rows that were discarded because they did not meet the specified criteria for the WHEN clause

■

Number of rows whose relevant fields were all null

■

Date cache statistics, if applicable

For example:

Table EMP:

25000 Rows successfully loaded.

2 Rows not loaded due to data errors.

0 Rows not loaded because all WHEN clauses were failed.

0 Rows not loaded because all fields were null.

Date Cache:

Max Size: 2000

Entries: 1000

Hits: 11000

Misses: 0

See Also:

Specifying a Value for the Date Cache on page 9-22 for information on how you can improve performance by adjusting the maximum size of the date cache

Summary Statistics

The Summary Statistics Section displays the following data:

■

Amount of space used:

SQL*Loader Log File Reference

8-5

Summary Statistics

■

■

–

For bind array (what was actually used, based on what was specified by

BINDSIZE

)

–

For other overhead (always required, independent of BINDSIZE)

Cumulative load statistics. That is, for all datafiles, the number of records that were:

–

Skipped

–

Read

–

Rejected

–

Discarded

Beginning and ending time of run

■

■

Total elapsed time

Total CPU time (includes all file I/O but may not include background Oracle

CPU time)

For example:

Space allocated for bind array: 65336 bytes (64 rows)

Space allocated for memory less bind array: 6470 bytes

Total logical records skipped: 0

Total logical records read: 7

Total logical records rejected: 0

Total logical records discarded: 0

Run began on Wed Feb 27 10:46:53 1990

Run ended on Wed Feb 27 10:47:17 1990

Elapsed time was: 00:00:15.62

CPU time was: 00:00:07.76

Oracle Statistics That Are Logged

The statistics that are reported to the log file vary, depending on the load type.

■

■

For conventional loads and direct loads of a nonpartitioned table, statistics reporting is unchanged from Oracle7.

For direct loads of a partitioned table, a per-partition statistics section is provided after the table-level statistics section.

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Additional Summary Statistics for Direct Path Loads and Multithreading

■

For a single-partition load, the partition name will be included in the table-level statistics section.

■

■

■

Information About Single-Partition Loads

The following information is logged when a single partition is loaded:

The table column description includes the partition name.

Error messages include the partition name.

Statistics listings include the partition name.

Statistics for Loading a Table

The following statistics are logged when a table is loaded:

■

■

■

Direct path load of a partitioned table reports per-partition statistics.

Conventional path load cannot report per-partition statistics.

For loading a nonpartitioned table, statistics are unchanged from Oracle7.

For conventional loads and direct loads of a nonpartitioned table, statistics reporting is unchanged from Oracle7.

If you request logging, but media recovery is not enabled, the load is not logged.

Additional Summary Statistics for Direct Path Loads and Multithreading

For direct path loads, the log contains the following additional data (the numbers in your log file will be different):

Column array rows: 20000

Stream buffer bytes: 256000

See Specifying the Number of Column Array Rows and Size of Stream Buffers on page 9-21 for information about the origin of these statistics.

Direct path loads on multiple-CPU systems have the option of using multithreading. If multithreading is enabled (the default behavior), the following additional statistics are logged (the numbers in your log will be different):

Total stream buffers loaded by SQL*Loader main thread: 102

Total stream buffers loaded by SQL*Loader load thread: 200

See Optimizing Direct Path Loads on Multiple-CPU Systems on page 9-23 for more information about multithreading.

SQL*Loader Log File Reference

8-7

Log File Created When EXTERNAL_TABLE=GENERATE_ONLY

Log File Created When EXTERNAL_TABLE=GENERATE_ONLY

When you use the external tables feature, you can place all of the SQL commands needed to do the load, as described in the control file, in the SQL*Loader log file. To do this, set the EXTERNAL_TABLE parameter to GENERATE_ONLY. The actual load can be done later without the use of SQL*Loader by executing these statements in

SQL*Plus.

To generate an example of the log file created when using EXTERNAL_

TABLE=GENERATE_ONLY

, execute the following command for case study 1 ( Case

Study 1: Loading Variable-Length Data on page 10-5): sqlldr scott/tiger ulcase1 EXTERNAL_TABLE=GENERATE_ONLY

The resulting log file looks as follows:

SQL*Loader: Release 9.2.0.1.0 - Production on Wed Feb 27 11:07:28 2002

(c) Copyright 2002 Oracle Corporation. All rights reserved.

Control File: ulcase1.ctl

Data File: ulcase1.ctl

Bad File: ulcase1.bad

Discard File: none specified

(Allow all discards)

Number to load: ALL

Number to skip: 0

Errors allowed: 50

Continuation: none specified

Path used: External Table

Table DEPT, loaded from every logical record.

Insert option in effect for this table: INSERT

Column Name Position Len Term Encl Datatype

------------------------------ ---------- ----- ---- ---- ---------------------

DEPTNO FIRST * , O(") CHARACTER

DNAME NEXT * , O(") CHARACTER

LOC NEXT * , O(") CHARACTER

CREATE DIRECTORY statements needed for files

------------------------------------------------------------------------

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Log File Created When EXTERNAL_TABLE=GENERATE_ONLY

CREATE DIRECTORY SYS_SQLLDR_XT_TMPDIR_00000 AS

’/private/adestore/krich/.ade/view_storage/krich_dev/rdbms/demo’

CREATE TABLE statement for external table:

------------------------------------------------------------------------

CREATE TABLE "SYS_SQLLDR_X_EXT_DEPT"

(

DEPTNO NUMBER(2),

DNAME VARCHAR2(14),

LOC VARCHAR2(13)

)

ORGANIZATION external

(

TYPE oracle_loader

DEFAULT DIRECTORY SYS_SQLLDR_XT_TMPDIR_00000

ACCESS PARAMETERS

(

RECORDS DELIMITED BY NEWLINE CHARACTERSET US7ASCII

BADFILE ’SYS_SQLLDR_XT_TMPDIR_00000’:’ulcase1.bad’

LOGFILE ’ulcase1.log_xt’

READSIZE 1048576

SKIP 20

FIELDS TERMINATED BY "," OPTIONALLY ENCLOSED BY ’"’ LDRTRIM

REJECT ROWS WITH ALL NULL FIELDS

(

DEPTNO CHAR(255)

TERMINATED BY "," OPTIONALLY ENCLOSED BY ’"’,

DNAME CHAR(255)

TERMINATED BY "," OPTIONALLY ENCLOSED BY ’"’,

LOC CHAR(255)

TERMINATED BY "," OPTIONALLY ENCLOSED BY ’"’

)

)

location

(

’ulcase1.ctl’

)

)REJECT LIMIT UNLIMITED

INSERT statements used to load internal tables:

------------------------------------------------------------------------

INSERT /*+ append */ INTO DEPT

(

SQL*Loader Log File Reference

8-9

Log File Created When EXTERNAL_TABLE=GENERATE_ONLY

DEPTNO,

DNAME,

LOC

)

SELECT

DEPTNO,

DNAME,

LOC

FROM "SYS_SQLLDR_X_EXT_DEPT" statements to cleanup objects created by previous statements:

------------------------------------------------------------------------

DROP TABLE "SYS_SQLLDR_X_EXT_DEPT"

DROP DIRECTORY SYS_SQLLDR_XT_TMPDIR_00000

Run began on Wed Feb 27 11:07:28 2002

Run ended on Wed Feb 27 11:07:34 2002

Elapsed time was: 00:00:06.13

CPU time was: 00:00:00.20

See Also:

■

■

EXTERNAL_TABLE on page 4-7

Part III, "External Tables"

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9

Conventional and Direct Path Loads

This chapter describes SQL*Loader’s conventional and direct path load methods.

The following topics are covered:

■

■

Data Loading Methods

Conventional Path Load

■

■

■

■

Direct Path Load

Using Direct Path Load

Optimizing Performance of Direct Path Loads

Optimizing Direct Path Loads on Multiple-CPU Systems

■

■

Avoiding Index Maintenance

Direct Loads, Integrity Constraints, and Triggers

■

■

Parallel Data Loading Models

General Performance Improvement Hints

For an example of using the direct path load method, see Case Study 6: Loading

Data Using the Direct Path Load Method on page 10-24. The other cases use the conventional path load method.

Data Loading Methods

SQL*Loader provides two methods for loading data:

■

Conventional Path Load

■

Direct Path Load

Conventional and Direct Path Loads

9-1

Data Loading Methods

A conventional path load executes SQL INSERT statements to populate tables in an

Oracle database. A direct path load eliminates much of the Oracle database overhead by formatting Oracle data blocks and writing the data blocks directly to the database files. A direct load does not compete with other users for database resources, so it can usually load data at near disk speed. Considerations inherent to direct path loads, such as restrictions, security, and backup implications, are discussed in this chapter.

The tables to be loaded must already exist in the database. SQL*Loader never creates tables. It loads existing tables that either already contain data or are empty.

The following privileges are required for a load:

■

■

You must have INSERT privileges on the table to be loaded.

You must have DELETE privileges on the table to be loaded, when using the

REPLACE

or TRUNCATE option to empty old data from the table before loading the new data in its place.

Figure 9–1 shows how conventional and direct path loads perform database writes.

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Data Loading Methods

Figure 9–1 Database Writes on SQL*Loader Direct Path and Conventional Path

SQL*Loader SQL*Loader User Processes

Record

Block

Generate SQL

Commands

Generate SQL

Commands

Direct

Path

Conventional

Path

Oracle Server

SQL Command Processing

Space Management

Get new extents

Adjust high-water mark

Find partial blocks

Fill partial blocks

Buffer Cache Management

- Manage queues

- Resolve contention

Buffer cache

Read Database

Blocks

Write Database

Blocks

Database

Conventional and Direct Path Loads

9-3

Conventional Path Load

Conventional Path Load

Conventional path load (the default) uses the SQL INSERT statement and a bind array buffer to load data into database tables. This method is used by all Oracle tools and applications.

When SQL*Loader performs a conventional path load, it competes equally with all other processes for buffer resources. This can slow the load significantly. Extra overhead is added as SQL commands are generated, passed to Oracle, and executed.

The Oracle database server looks for partially filled blocks and attempts to fill them on each insert. Although appropriate during normal use, this can slow bulk loads dramatically.

See Also:

Discontinued Conventional Path Loads on page 5-24

Conventional Path Load of a Single Partition

By definition, a conventional path load uses SQL INSERT statements. During a conventional path load of a single partition, SQL*Loader uses the partition-extended syntax of the INSERT statement, which has the following form:

INSERT INTO TABLE T PARTITION (P) VALUES ...

The SQL layer of the Oracle kernel determines if the row being inserted maps to the specified partition. If the row does not map to the partition, the row is rejected, and the SQL*Loader log file records an appropriate error message.

When to Use a Conventional Path Load

If load speed is most important to you, you should use direct path load because it is faster than conventional path load. However, certain restrictions on direct path loads may require you to use a conventional path load. You should use a conventional path load in the following situations:

■

■

When accessing an indexed table concurrently with the load, or when applying inserts or updates to a nonindexed table concurrently with the load

To use a direct path load (with the exception of parallel loads), SQL*Loader must have exclusive write access to the table and exclusive read/write access to any indexes.

When loading data into a clustered table

A direct path load does not support loading of clustered tables.

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Direct Path Load

■

■

■

When loading a relatively small number of rows into a large indexed table

During a direct path load, the existing index is copied when it is merged with the new index keys. If the existing index is very large and the number of new keys is very small, then the index copy time can offset the time saved by a direct path load.

When loading a relatively small number of rows into a large table with referential and column-check integrity constraints

Because these constraints cannot be applied to rows loaded on the direct path, they are disabled for the duration of the load. Then they are applied to the whole table when the load completes. The costs could outweigh the savings for a very large table and a small number of new rows.

When loading records and you want to ensure that a record is rejected under any of the following circumstances:

–

If the record, upon insertion, causes an Oracle error

–

If the record is formatted incorrectly, so that SQL*Loader cannot find field boundaries

–

If the record violates a constraint or tries to make a unique index non-unique

Direct Path Load

Instead of filling a bind array buffer and passing it to the Oracle database server with a SQL INSERT statement, a direct path load uses the direct path API to pass the data to be loaded to the load engine in the server. The load engine builds a column array structure from the data passed to it.

The direct path load engine uses the column array structure to format Oracle data blocks and build index keys. The newly formatted database blocks are written directly to the database (multiple blocks per I/O request using asynchronous writes if the host platform supports asynchronous I/O).

Internally, multiple buffers are used for the formatted blocks. While one buffer is being filled, one or more buffers are being written if asynchronous I/O is available on the host platform. Overlapping computation with I/O increases load performance.

See Also:

Discontinued Direct Path Loads on page 5-24

Conventional and Direct Path Loads

9-5

Direct Path Load

Data Conversion During Direct Path Loads

During a direct path load, data conversion occurs on the client side rather than on the server side. This means that NLS parameters in the initialization parameter file

(server-side language handle) will not be used. To override this behavior, you can specify a format mask in the SQL*Loader control file which is equivalent to the setting of the NLS parameter in the initialization parameter file, or set the appropriate environment variable. For example, to specify a date format for a field, you can either set the date format in the SQL*Loader control file as shown in

Example 9–1 or set an NLS_DATE_FORMAT environment variable as shown in

Example 9–2 .

Example 9–1 Setting the Date Format in the SQL*Loader Control File

LOAD DATA

INFILE ’data.dat’

INSERT INTO TABLE emp

FIELDS TERMINATED BY "|"

(

EMPNO NUMBER(4) NOT NULL,

ENAME CHAR(10),

JOB CHAR(9),

MGR NUMBER(4),

HIREDATE DATE ’YYYYMMDD’,

SAL NUMBER(7,2),

COMM NUMBER(7,2),

DEPTNO NUMBER(2)

)

Example 9–2 Setting an NLS_DATE_FORMAT Environment Variable

On UNIX bourne or korn shell:

% NLS_DATE_FORMAT=’YYYYMMDD’

% export NLS_DATE_FORMAT

On UNIX csh:

%setenv NLS_DATE_FORMAT=’YYYYMMDD’

Direct Path Load of a Partitioned or Subpartitioned Table

When loading a partitioned or subpartitioned table, SQL*Loader partitions the rows and maintains indexes (which can also be partitioned). Note that a direct path load

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Direct Path Load of a partitioned or subpartitioned table can be quite resource-intensive for tables with many partitions or subpartitions.

Note:

If you are performing a direct path load into multiple partitions and a space error occurs, the load is rolled back to the last commit point. If there was no commit point, then the entire load is rolled back. This ensures that no data encountered after the space error is written out to a different partition.

You can use the ROWS parameter to specify the frequency of the commit points. If the ROWS parameter is not specified, the entire load is rolled back.

Direct Path Load of a Single Partition or Subpartition

When loading a single partition of a partitioned or subpartitioned table,

SQL*Loader partitions the rows and rejects any rows that do not map to the partition or subpartition specified in the SQL*Loader control file. Local index partitions that correspond to the data partition or subpartition being loaded are maintained by SQL*Loader. Global indexes are not maintained on single partition or subpartition direct path loads. During a direct path load of a single partition,

SQL*Loader uses the partition-extended syntax of the LOAD statement, which has either of the following forms:

LOAD INTO TABLE T PARTITION (P) VALUES ...

LOAD INTO TABLE T SUBPARTITION (P) VALUES ...

While you are loading a partition of a partitioned or subpartitioned table, you are also allowed to perform DML operations on, and direct path loads of, other partitions in the table.

Although a direct path load minimizes database processing, several calls to the

Oracle database server are required at the beginning and end of the load to initialize and finish the load, respectively. Also, certain DML locks are required during load initialization and are released when the load completes. The following operations occur during the load: index keys are built and put into a sort, and space management routines are used to get new extents when needed and to adjust the upper boundary (high-water mark) for a data savepoint. See Using Data Saves to

Protect Against Data Loss on page 9-13 for information on adjusting the upper boundary.

Conventional and Direct Path Loads

9-7

Direct Path Load

Advantages of a Direct Path Load

A direct path load is faster than the conventional path for the following reasons:

■

■

■

■

■

■

■

■

Partial blocks are not used, so no reads are needed to find them, and fewer writes are performed.

SQL*Loader need not execute any SQL INSERT statements; therefore, the processing load on the Oracle database is reduced.

A direct path load calls on Oracle to lock tables and indexes at the start of the load and releases them when the load is finished. A conventional path load calls

Oracle once for each array of rows to process a SQL INSERT statement.

A direct path load uses multiblock asynchronous I/O for writes to the database files.

During a direct path load, processes perform their own write I/O, instead of using Oracle’s buffer cache. This minimizes contention with other Oracle users.

The sorted indexes option available during direct path loads allows you to presort data using high-performance sort routines that are native to your system or installation.

When a table to be loaded is empty, the presorting option eliminates the sort and merge phases of index-building. The index is filled in as data arrives.

Protection against instance failure does not require redo log file entries during direct path loads. Therefore, no time is required to log the load when:

–

Oracle is operating in NOARCHIVELOG mode

–

The UNRECOVERABLE parameter is set to Y

–

The object being loaded has the NOLOG attribute set

See Instance Recovery and Direct Path Loads on page 9-15.

Restrictions on Using Direct Path Loads

The following conditions must be satisfied for you to use the direct path load method:

■

■

Tables are not clustered.

Tables to be loaded do not have any active transactions pending.

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Direct Path Load

■

To check for this condition, use the Oracle Enterprise Manager command

MONITOR TABLE

to find the object ID for the tables you want to load. Then use the command MONITOR LOCK to see if there are any locks on the tables.

For versions of the Oracle database server prior to 9i, you can only perform a

SQL*Loader direct path load when the client and server are the same version.

This also means that you cannot perform a direct path load of Oracle9i data into a database of an earlier version. For example, you cannot use direct path load to load data from a release 9.0.1 database into a release 8.1.7 database.

However, beginning with Oracle9i, you can perform a SQL*Loader direct path load between different versions as long as both the client and server are version

9i or later. For example, you can perform a direct path load from a release 9.0.1

database into a release 9.2 database.

The following features are not available with direct path load.

■

Loading VARRAYs

■

■

Loading a parent table together with a child table

Loading BFILE columns

Restrictions on a Direct Path Load of a Single Partition

In addition to the previously listed restrictions, loading a single partition has the following restrictions:

■

The table that the partition is a member of cannot have any global indexes defined on it.

■

■

Enabled referential and check constraints on the table that the partition is a member of are not allowed.

Enabled triggers are not allowed.

When to Use a Direct Path Load

If none of the previous restrictions apply, you should use a direct path load when:

■

■

You have a large amount of data to load quickly. A direct path load can quickly load and index large amounts of data. It can also load data into either an empty or nonempty table.

You want to load data in parallel for maximum performance. See Parallel Data

Loading Models on page 9-30.

Conventional and Direct Path Loads

9-9

Using Direct Path Load

Integrity Constraints

All integrity constraints are enforced during direct path loads, although not necessarily at the same time. NOT NULL constraints are enforced during the load.

Records that fail these constraints are rejected.

UNIQUE

constraints are enforced both during and after the load. A record that violates a UNIQUE constraint is not rejected (the record is not available in memory when the constraint violation is detected).

Integrity constraints that depend on other rows or tables, such as referential constraints, are disabled before the direct path load and must be reenabled afterwards. If REENABLE is specified, SQL*Loader can reenable them automatically at the end of the load. When the constraints are reenabled, the entire table is checked. Any rows that fail this check are reported in the specified error log. See

Direct Loads, Integrity Constraints, and Triggers on page 9-25.

Field Defaults on the Direct Path

Default column specifications defined in the database are not available when you use direct path loading. Fields for which default values are desired must be specified with the DEFAULTIF clause. If a DEFAULTIF clause is not specified and the field is NULL, then a null value is inserted into the database.

Loading into Synonyms

You can load data into a synonym for a table during a direct path load, but the synonym must point directly to a table. It cannot be a synonym for a view, or a synonym for another synonym.

Using Direct Path Load

This section explains how to use the SQL*Loader direct path load method.

Setting Up for Direct Path Loads

To prepare the database for direct path loads, you must run the setup script, catldr

.sql, to create the necessary views. You need only run this script once for each database you plan to do direct loads to. You can run this script during database installation if you know then that you will be doing direct loads.

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Using Direct Path Load

Specifying a Direct Path Load

To start SQL*Loader in direct path load mode, set the DIRECT parameter to true on the command line or in the parameter file, if used, in the format:

DIRECT=true

See Also:

■

■

■

Case Study 6: Loading Data Using the Direct Path Load

Method on page 10-24

Optimizing Performance of Direct Path Loads on page 9-17 for information about parameters you can use to optimize performance of direct path loads

Optimizing Direct Path Loads on Multiple-CPU Systems on page 9-23 if you are doing a direct path load on a multiple-CPU system or across systems

Building Indexes

You can improve performance of direct path loads by using temporary storage.

After each block is formatted, the new index keys are put in a sort (temporary) segment. The old index and the new keys are merged at load finish time to create the new index. The old index, sort (temporary) segment, and new index segment all require storage until the merge is complete. Then the old index and temporary segment are removed.

During a conventional path load, every time a row is inserted the index is updated.

This method does not require temporary storage space, but it does add processing time.

Improving Performance

To improve performance on systems with limited memory, use the SINGLEROW parameter. For more information, see SINGLEROW Option on page 5-38.

Note:

If, during a direct load, you have specified that the data is to be presorted and the existing index is empty, a temporary segment is not required, and no merge occurs—the keys are put directly into the index. See Optimizing Performance of Direct Path Loads on page 9-17 for more information.

Conventional and Direct Path Loads

9-11

Using Direct Path Load

When multiple indexes are built, the temporary segments corresponding to each index exist simultaneously, in addition to the old indexes. The new keys are then merged with the old indexes, one index at a time. As each new index is created, the old index and the corresponding temporary segment are removed.

See Also:

Oracle9i Database Administrator’s Guide for information on how to estimate index size and set storage parameters

Temporary Segment Storage Requirements

To estimate the amount of temporary segment space needed for storing the new index keys (in bytes), use the following formula:

1.3 * key_storage

In this formula, key storage is defined as follows: key_storage = (number_of_rows) *

( 10 + sum_of_column_sizes + number_of_columns )

The columns included in this formula are the columns in the index. There is one length byte per column, and 10 bytes per row are used for a ROWID and additional overhead.

The constant 1.3 reflects the average amount of extra space needed for sorting. This value is appropriate for most randomly ordered data. If the data arrives in exactly opposite order, twice the key-storage space is required for sorting, and the value of this constant would be 2.0. That is the worst case.

If the data is fully sorted, only enough space to store the index entries is required, and the value of this constant would be 1.0. See Presorting Data for Faster Indexing on page 9-18 for more information.

Indexes Left in an Unusable State

SQL*Loader leaves indexes in an Index Unusable state when the data segment being loaded becomes more up-to-date than the index segments that index it.

Any SQL statement that tries to use an index that is in an Index Unusable state returns an error. The following conditions cause a direct path load to leave an index or a partition of a partitioned index in an Index Unusable state:

■

■

SQL*Loader runs out of space for the index and cannot update the index.

The data is not in the order specified by the SORTED INDEXES clause.

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Using Direct Path Load

■

■

■

There is an instance failure, or the Oracle shadow process fails while building the index.

There are duplicate keys in a unique index.

Data savepoints are being used, and the load fails or is terminated by a keyboard interrupt after a data savepoint occurred.

To determine if an index is in an Index Unusable state, you can execute a simple query:

SELECT INDEX_NAME, STATUS

FROM USER_INDEXES

WHERE TABLE_NAME = ’tablename’ ;

If you are not the owner of the table, then search ALL_INDEXES or DBA_INDEXES instead of USER_INDEXES.

To determine if an index partition is in an unusable state, you can execute the following query:

SELECT INDEX_NAME,

PARTITION_NAME,

STATUS FROM USER_IND_PARTITIONS

WHERE STATUS != ’ VALID ’;

If you are not the owner of the table, then search ALL_IND_PARTITIONS and DBA_

IND_PARTITIONS

instead of USER_IND_PARTITIONS.

Using Data Saves to Protect Against Data Loss

You can use data saves to protect against loss of data due to instance failure. All data loaded up to the last savepoint is protected against instance failure. To continue the load after an instance failure, determine how many rows from the input file were processed before the failure, then use the SKIP parameter to skip those processed rows.

If there were any indexes on the table, drop them before continuing the load, then re-create them after the load. See Data Recovery During Direct Path Loads on page 9-15 for more information on media and instance recovery.

Conventional and Direct Path Loads

9-13

Using Direct Path Load

Note:

Indexes are not protected by a data save, because

SQL*Loader does not build indexes until after data loading completes. (The only time indexes are built during the load is when presorted data is loaded into an empty table, but these indexes are also unprotected.)

Using the ROWS Parameter

The ROWS parameter determines when data saves occur during a direct path load.

The value you specify for ROWS is the number of rows you want SQL*Loader to read from the input file before saving inserts in the database.

The number of rows you specify for a data save is an approximate number. Direct loads always act on full data buffers that match the format of Oracle database blocks. So, the actual number of data rows saved is rounded up to a multiple of the number of rows in a database block.

SQL*Loader always reads the number of rows needed to fill a database block.

Discarded and rejected records are then removed, and the remaining records are inserted into the database. The actual number of rows inserted before a save is the value you specify, rounded up to the number of rows in a database block, minus the number of discarded and rejected records.

A data save is an expensive operation. The value for ROWS should be set high enough so that a data save occurs once every 15 minutes or longer. The intent is to provide an upper boundary (high-water mark) on the amount of work that is lost when an instance failure occurs during a long-running direct path load. Setting the value of ROWS to a small number adversely affects performance.

Data Save Versus Commit

In a conventional load, ROWS is the number of rows to read before a commit. A direct load data save is similar to a conventional load commit, but it is not identical.

The similarities are as follows:

■

A data save will make the rows visible to other users.

■

Rows cannot be rolled back after a data save.

The major difference is that in a direct path load data save, the indexes will be unusable (in Index Unusable state) until the load completes.

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Using Direct Path Load

Data Recovery During Direct Path Loads

SQL*Loader provides full support for data recovery when using the direct path load method. There are two main types of recovery:

■

Media recovery - recovery from the loss of a database file. You must be operating in ARCHIVELOG mode to recover after you lose a database file.

■

Instance recovery - recovery from a system failure in which in-memory data was changed but lost due to the failure before it was written to disk. The Oracle database server can always recover from instance failures, even when redo logs are not archived

See Also:

Oracle9i Database Administrator’s Guide for more information about recovery

Media Recovery and Direct Path Loads

If redo log file archiving is enabled (you are operating in ARCHIVELOG mode),

SQL*Loader logs loaded data when using the direct path, making media recovery possible. If redo log archiving is not enabled (you are operating in NOARCHIVELOG mode), then media recovery is not possible.

To recover a database file that was lost while it was being loaded, use the same method that you use to recover data loaded with the conventional path:

1.

2.

Restore the most recent backup of the affected database file.

Recover the tablespace using the RECOVER command.

See Also:

Oracle9i User-Managed Backup and Recovery Guide for more information on the RECOVER command

Instance Recovery and Direct Path Loads

Because SQL*Loader writes directly to the database files, all rows inserted up to the last data save will automatically be present in the database files if the instance is restarted. Changes do not need to be recorded in the redo log file to make instance recovery possible.

If an instance failure occurs, the indexes being built may be left in an Index

Unusable state. Indexes that are Unusable must be rebuilt before you can use the table or partition. See Indexes Left in an Unusable State on page 9-12 for information on how to determine if an index has been left in Index Unusable state.

Conventional and Direct Path Loads

9-15

Using Direct Path Load

Loading LONG Data Fields

Data that is longer than SQL*Loader’s maximum buffer size can be loaded on the direct path by using LOBs. You can improve performance when doing this by using a large streamsize value.

See Also:

■

■

Loading LOBs on page 7-18

Specifying the Number of Column Array Rows and Size of

Stream Buffers on page 9-21

You could also load data that is longer than the maximum buffer size by using the

PIECED

parameter, as described in the next section, but Oracle Corporation highly recommends that you use LOBs instead.

Loading Data As PIECED

The PIECED parameter can be used to load data in sections, if the data is in the last column of the logical record.

Declaring a column as PIECED informs the direct path loader that a LONG field might be split across multiple physical records (pieces). In such cases, SQL*Loader processes each piece of the LONG field as it is found in the physical record. All the pieces are read before the record is processed. SQL*Loader makes no attempt to materialize the LONG field before storing it; however, all the pieces are read before the record is processed.

The following restrictions apply when you declare a column as PIECED:

■

■

This option is only valid on the direct path.

Only one field per table may be PIECED.

■

■

■

■

■

The PIECED field must be the last field in the logical record.

The PIECED field may not be used in any WHEN, NULLIF, or DEFAULTIF clauses.

The PIECED field’s region in the logical record must not overlap with any other field’s region.

The PIECED corresponding database column may not be part of the index.

It may not be possible to load a rejected record from the bad file if it contains a

PIECED

field.

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Optimizing Performance of Direct Path Loads

For example, a PIECED field could span 3 records. SQL*Loader loads the piece from the first record and then reuses the buffer for the second buffer. After loading the second piece, the buffer is reused for the third record. If an error is then discovered, only the third record is placed in the bad file because the first two records no longer exist in the buffer. As a result, the record in the bad file would not be valid.

Optimizing Performance of Direct Path Loads

You can control the time and temporary storage used during direct path loads.

To minimize time:

■

Preallocate storage space

■

■

Presort the data

Perform infrequent data saves

■

■

Minimize use of the redo log

Specify the number of column array rows and the size of the stream buffer

■

Specify a date cache value

To minimize space:

■

■

When sorting data before the load, sort data on the index that requires the most temporary storage space

Avoid index maintenance during the load

Preallocating Storage for Faster Loading

SQL*Loader automatically adds extents to the table if necessary, but this process takes time. For faster loads into a new table, allocate the required extents when the table is created.

To calculate the space required by a table, see the information about managing database files in the Oracle9i Database Administrator’s Guide. Then use the INITIAL or MINEXTENTS clause in the SQL CREATE TABLE statement to allocate the required space.

Another approach is to size extents large enough so that extent allocation is infrequent.

Conventional and Direct Path Loads

9-17

Optimizing Performance of Direct Path Loads

Presorting Data for Faster Indexing

You can improve the performance of direct path loads by presorting your data on indexed columns. Presorting minimizes temporary storage requirements during the load. Presorting also allows you to take advantage of high-performance sorting routines that are optimized for your operating system or application.

If the data is presorted and the existing index is not empty, then presorting minimizes the amount of temporary segment space needed for the new keys. The sort routine appends each new key to the key list.

Instead of requiring extra space for sorting, only space for the keys is needed. To calculate the amount of storage needed, use a sort factor of 1.0 instead of 1.3. For more information on estimating storage requirements, see Temporary Segment

Storage Requirements on page 9-12.

If presorting is specified and the existing index is empty, then maximum efficiency is achieved. The new keys are simply inserted into the index. Instead of having a temporary segment and new index existing simultaneously with the empty, old index, only the new index exists. So, temporary storage is not required, and time is saved.

SORTED INDEXES Clause

The SORTED INDEXES clause identifies the indexes on which the data is presorted.

This clause is allowed only for direct path loads. See Case Study 6: Loading Data

Using the Direct Path Load Method on page 10-24 for an example.

Generally, you specify only one index in the SORTED INDEXES clause, because data that is sorted for one index is not usually in the right order for another index. When the data is in the same order for multiple indexes, however, all indexes can be specified at once.

All indexes listed in the SORTED INDEXES clause must be created before you start the direct path load.

Unsorted Data

If you specify an index in the SORTED INDEXES clause, and the data is not sorted for that index, then the index is left in an Index Unusable state at the end of the load. The data is present, but any attempt to use the index results in an error. Any index that is left in an Index Unusable state must be rebuilt after the load.

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Multiple-Column Indexes

If you specify a multiple-column index in the SORTED INDEXES clause, the data should be sorted so that it is ordered first on the first column in the index, next on the second column in the index, and so on.

For example, if the first column of the index is city, and the second column is last name; then the data should be ordered by name within each city, as in the following list:

Albuquerque Adams

Albuquerque Hartstein

Albuquerque Klein

... ...

Boston Andrews

Boston Bobrowski

Boston Heigham

... ...

Choosing the Best Sort Order

For the best overall performance of direct path loads, you should presort the data based on the index that requires the most temporary segment space. For example, if the primary key is one numeric column, and the secondary key consists of three text columns, then you can minimize both sort time and storage requirements by presorting on the secondary key.

To determine the index that requires the most storage space, use the following procedure:

1.

For each index, add up the widths of all columns in that index.

2.

3.

4.

For a single-table load, pick the index with the largest overall width.

For each table in a multiple-table load, identify the index with the largest overall width for each table. If the same number of rows are to be loaded into each table, then again pick the index with the largest overall width. Usually, the same number of rows are loaded into each table.

If a different number of rows are to be loaded into the indexed tables in a multiple-table load, then multiply the width of each index identified in step 3 by the number of rows that are to be loaded into that index, and pick the index with the largest result.

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Optimizing Performance of Direct Path Loads

Infrequent Data Saves

Frequent data saves resulting from a small ROWS value adversely affect the performance of a direct path load. Because direct path loads can be many times faster than conventional loads, the value of ROWS should be considerably higher for a direct load than it would be for a conventional load.

During a data save, loading stops until all of SQL*Loader’s buffers are successfully written. You should select the largest value for ROWS that is consistent with safety. It is a good idea to determine the average time to load a row by loading a few thousand rows. Then you can use that value to select a good value for ROWS.

For example, if you can load 20,000 rows per minute, and you do not want to repeat more than 10 minutes of work after an interruption, then set ROWS to be 200,000

(20,000 rows/minute * 10 minutes).

Minimizing Use of the Redo Log

One way to speed a direct load dramatically is to minimize use of the redo log.

There are three ways to do this. You can disable archiving, you can specify that the load is UNRECOVERABLE, or you can set the NOLOG attribute of the objects being loaded. This section discusses all methods.

Disabling Archiving

If archiving is disabled, direct path loads do not generate full image redo. Use the

ARCHIVELOG

and NOARCHIVELOG parameters to set the archiving mode. See the

Oracle9i Database Administrator’s Guide for more information about archiving.

Specifying the UNRECOVERABLE Parameter

To save time and space in the redo log file, use the UNRECOVERABLE parameter when you load data. An UNRECOVERABLE load does not record loaded data in the redo log file; instead, it generates invalidation redo.

The UNRECOVERABLE parameter applies to all objects loaded during the load session (both data and index segments). Therefore, media recovery is disabled for the loaded table, although database changes by other users may continue to be logged.

Note:

Because the data load is not logged, you may want to make a backup of the data after loading.

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If media recovery becomes necessary on data that was loaded with the

UNRECOVERABLE

parameter, the data blocks that were loaded are marked as logically corrupted.

To recover the data, drop and re-create the data. It is a good idea to do backups immediately after the load to preserve the otherwise unrecoverable data.

By default, a direct path load is RECOVERABLE.

Setting the NOLOG Attribute

If a data or index segment has the NOLOG attribute set, then full image redo logging is disabled for that segment (invalidation redo is generated.) Use of the NOLOG attribute allows a finer degree of control over the objects that are not logged.

Specifying the Number of Column Array Rows and Size of Stream Buffers

The number of column array rows determines the number of rows loaded before the stream buffer is built. The STREAMSIZE parameter specifies the size (in bytes) of the data stream sent from the client to the server.

Use the COLUMNARRAYROWS parameter to specify a value for the number of column array rows.

Use the STREAMSIZE parameter to specify the size for direct path stream buffers.

The optimal values for these parameters vary, depending on the system, input datatypes, and Oracle column datatypes used. When you are using optimal values for your particular configuration, the elapsed time in the SQL*Loader log file should go down.

To see a list of default values for these and other parameters, invoke SQL*Loader without any parameters, as described in Invoking SQL*Loader on page 4-1.

Note:

You should monitor process paging activity, because if paging becomes excessive, performance can be significantly degraded. You may need to lower the values for READSIZE,

STREAMSIZE

, and COLUMNARRAYROWS to avoid excessive paging.

It can be particularly useful to specify the number of column array rows and size of the steam buffer when you perform direct path loads on multiple-CPU systems. See

Optimizing Direct Path Loads on Multiple-CPU Systems on page 9-23 for more information.

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Optimizing Performance of Direct Path Loads

Specifying a Value for the Date Cache

If you are performing a direct path load in which the same date or timestamp values are loaded many times, a large percentage of total load time can end up being used for converting date and timestamp data. This is especially true if multiple date columns are being loaded. In such a case, it may be possible to improve performance by using the SQL*Loader date cache.

The date cache reduces the number of date conversions done when many duplicate values are present in the input data. It allows you to specify the number of unique dates anticipated during the load.

The date cache is enabled by default. To completely disable the date cache, set it to

0.

The default date cache size is 1000 elements. If the default is used and the number of unique input values loaded exceeds 1000, then the date cache is automatically disabled for that table. This prevents excessive and unnecessary lookup times that could affect performance. However, if instead of using the default, you specify a nonzero value for the date cache and it is exceeded, the date cache is not disabled.

Instead, any input data that exceeded the maximum is explicitly converted using the appropriate conversion routines.

The date cache can be associated with only one table. No date cache sharing can take place across tables. A date cache is created for a table only if all of the following conditions are true:

■

The DATE_CACHE parameter is not set to 0

■

One or more date values, timestamp values, or both are being loaded that require datatype conversion in order to be stored in the table

■

The load is a direct path load

Date cache statistics are written to the log file. You can use those statistics to improve direct path load performance as follows:

■

■

■

If the number of cache entries is less than the cache size and there are no cache misses, then the cache size could safely be set to a smaller value.

If the number of cache hits (entries for which there are duplicate values) is small and the number of cache misses is large, then the cache size should be increased. Be aware that if the cache size is increased too much, it may cause other problems such as excessive paging or too much memory usage.

If most of the input date values are unique, the date cache will not enhance performance and therefore should not be used.

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Note:

Date cache statistics are not written to the SQL*Loader log file if the cache was active by default and disabled because the maximum was exceeded.

If increasing the cache size does not improve performance, revert to the default behavior or set the cache size to 0. The overall performance improvement also depends on the datatypes of the other columns being loaded. Improvement will be greater for cases in which the total number of date columns loaded is large compared to other types of data loaded.

See Also:

■

■

DATE_CACHE on page 4-5

Table Load Information on page 8-5 for an example of how date cache statistics are presented in the SQL*Loader log file

Optimizing Direct Path Loads on Multiple-CPU Systems

If you are performing direct path loads on a multiple-CPU system, SQL*Loader uses multithreading by default. A multiple-CPU system in this case is defined as a single system that has two or more CPUs.

Multithreaded loading means that, when possible, conversion of the column arrays to stream buffers and stream buffer loading are performed in parallel. This optimization works best when:

■

■

Column arrays are large enough to generate multiple direct path stream buffers for loads

Data conversions are required from input field datatypes to Oracle column datatypes

The conversions are performed in parallel with stream buffer loading.

The status of this process is recorded in the SQL*Loader log file, as shown in the following sample portion of a log:

Total stream buffers loaded by SQL*Loader main thread: 47

Total stream buffers loaded by SQL*Loader load thread: 180

Column array rows: 1000

Stream buffer bytes: 256000

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Avoiding Index Maintenance

In this example, the SQL*Loader load thread has offloaded the SQL*Loader main thread, allowing the main thread to build the next stream buffer while the load thread loads the current stream on the server.

The goal is to have the load thread perform as many stream buffer loads as possible.

This can be accomplished by increasing the number of column array rows, decreasing the stream buffer size, or both. You can monitor the elapsed time in the

SQL*Loader log file to determine whether your changes are having the desired effect. See Specifying the Number of Column Array Rows and Size of Stream

Buffers on page 9-21 for more information.

On single-CPU systems, optimization is turned off by default. When the server is on another system, performance may improve if you manually turn on multithreading.

To turn the multithreading option on or off, use the MULTITHREADING parameter at the SQL*Loader command line or specify it in your SQL*Loader control file.

See Also:

Oracle Call Interface Programmer’s Guide for more information about the concepts of direct path loading

Avoiding Index Maintenance

For both the conventional path and the direct path, SQL*Loader maintains all existing indexes for a table.

To avoid index maintenance, use one of the following methods:

■

■

■

Drop the indexes prior to the beginning of the load.

Mark selected indexes or index partitions as Index Unusable prior to the beginning of the load and use the SKIP_UNUSABLE_INDEXES parameter.

Use the SKIP_INDEX_MAINTENANCE parameter (direct path only, use with caution).

By avoiding index maintenance, you minimize the amount of space required during a direct path load, in the following ways:

■

You can build indexes one at a time, reducing the amount of sort (temporary) segment space that would otherwise be needed for each index.

■

Only one index segment exists when an index is built, instead of the three segments that temporarily exist when the new keys are merged into the old index to make the new index.

Avoiding index maintenance is quite reasonable when the number of rows to be loaded is large compared to the size of the table. But if relatively few rows are

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Direct Loads, Integrity Constraints, and Triggers added to a large table, then the time required to resort the indexes may be excessive.

In such cases, it is usually better to use the conventional path load method, or to use the SINGLEROW parameter of SQL*Loader. For more information, see SINGLEROW

Option on page 5-38.

Direct Loads, Integrity Constraints, and Triggers

With the conventional path load method, arrays of rows are inserted with standard

SQL INSERT statements—integrity constraints and insert triggers are automatically applied. But when you load data with the direct path, SQL*Loader disables some integrity constraints and all database triggers. This section discusses the implications of using direct path loads with respect to these features.

Integrity Constraints

During a direct path load, some integrity constraints are automatically disabled.

Others are not. For a description of the constraints, see the information on maintaining data integrity in the Oracle9i Application Developer’s Guide -

Fundamentals.

■

Enabled Constraints

The constraints that remain in force are:

NOT NULL

■

UNIQUE

■

PRIMARY KEY

(unique-constraints on not-null columns)

NOT NULL constraints are checked at column array build time. Any row that violates the NOT NULL constraint is rejected.

UNIQUE

constraints are verified when indexes are rebuilt at the end of the load. The index will be left in an Index Unusable state if a violation of a UNIQUE constraint is detected. See Indexes Left in an Unusable State on page 9-12.

■

■

Disabled Constraints

During a direct path load, the following constraints are automatically disabled by default:

CHECK

constraints

Referential constraints (FOREIGN KEY)

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Direct Loads, Integrity Constraints, and Triggers

You can override the disabling of CHECK constraints by specifying the EVALUATE_

CHECK_CONSTRAINTS

clause. SQL*Loader will then evaluate CHECK constraints during a direct path load. Any row that violates the CHECK constraint is rejected.

Reenable Constraints

When the load completes, the integrity constraints will be reenabled automatically if the REENABLE clause is specified. The syntax for the REENABLE clause is as follows:

EVALUATE_CHECK_CONSTRAINTS REENABLE DISABLED_CONSTRAINTS

EXCEPTIONS table WHEN field_condition

The optional parameter DISABLED_CONSTRAINTS is provided for readability. If the EXCEPTIONS clause is included, the table must already exist, and you must be able to insert into it. This table contains the ROWIDs of all rows that violated one of the integrity constraints. It also contains the name of the constraint that was violated. See Oracle9i SQL Reference for instructions on how to create an exceptions table.

The SQL*Loader log file describes the constraints that were disabled, the ones that were reenabled, and what error, if any, prevented reenabling or validating of each constraint. It also contains the name of the exceptions table specified for each loaded table.

If the REENABLE clause is not used, then the constraints must be reenabled manually, at which time all rows in the table are verified. If the Oracle database server finds any errors in the new data, error messages are produced. The names of violated constraints and the ROWIDs of the bad data are placed in an exceptions table, if one is specified.

If the REENABLE clause is used, SQL*Loader automatically reenables the constraint and then verifies all new rows. If no errors are found in the new data, SQL*Loader automatically marks the constraint as validated. If any errors are found in the new data, error messages are written to the log file and SQL*Loader marks the status of the constraint as ENABLE NOVALIDATE. The names of violated constraints and the

ROWIDs of the bad data are placed in an exceptions table, if one is specified.

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Note:

Normally, when a table constraint is left in an ENABLE

NOVALIDATE

state, new data can be inserted into the table but no new invalid data may be inserted. However, SQL*Loader direct path load does not enforce this rule. Thus, if subsequent direct path loads are performed with invalid data, the invalid data will be inserted but the same error reporting and exception table processing as described previously will take place. In this scenario the exception table may contain duplicate entries if it is not cleared out before each load. Duplicate entries can easily be filtered out by performing a query such as the following:

SELECT UNIQUE * FROM exceptions_table;

Note:

Because referential integrity must be reverified for the entire table, performance may be improved by using the conventional path, instead of the direct path, when a small number of rows are to be loaded into a very large table.

Database Insert Triggers

Table insert triggers are also disabled when a direct path load begins. After the rows are loaded and indexes rebuilt, any triggers that were disabled are automatically reenabled. The log file lists all triggers that were disabled for the load. There should not be any errors reenabling triggers.

Unlike integrity constraints, insert triggers are not reapplied to the whole table when they are enabled. As a result, insert triggers do not fire for any rows loaded on the direct path. When using the direct path, the application must ensure that any behavior associated with insert triggers is carried out for the new rows.

Replacing Insert Triggers with Integrity Constraints

Applications commonly use insert triggers to implement integrity constraints. Most of these application insert triggers are simple enough that they can be replaced with

Oracle’s automatic integrity constraints.

When Automatic Constraints Cannot Be Used

Sometimes an insert trigger cannot be replaced with Oracle’s automatic integrity constraints. For example, if an integrity check is implemented with a table lookup in

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Direct Loads, Integrity Constraints, and Triggers an insert trigger, then automatic check constraints cannot be used, because the automatic constraints can only reference constants and columns in the current row.

This section describes two methods for duplicating the effects of such a trigger.

Preparation

Before either method can be used, the table must be prepared. Use the following general guidelines to prepare the table:

1.

2.

Before the load, add a 1-byte or 1-character column to the table that marks rows as "old data" or "new data."

Let the value of null for this column signify "old data," because null columns do not take up space.

3.

When loading, flag all loaded rows as "new data" with SQL*Loader’s

CONSTANT

parameter.

After following this procedure, all newly loaded rows are identified, making it possible to operate on the new data without affecting the old rows.

Using an Update Trigger

Generally, you can use a database update trigger to duplicate the effects of an insert trigger. This method is the simplest. It can be used whenever the insert trigger does not raise any exceptions.

1.

Create an update trigger that duplicates the effects of the insert trigger.

2.

3.

Copy the trigger. Change all occurrences of "new.column_name" to

" old.column_name"

.

Replace the current update trigger, if it exists, with the new one.

Update the table, changing the "new data" flag to null, thereby firing the update trigger.

4.

Restore the original update trigger, if there was one.

Depending on the behavior of the trigger, it may be necessary to have exclusive update access to the table during this operation, so that other users do not inadvertently apply the trigger to rows they modify.

Duplicating the Effects of Exception Conditions

If the insert trigger can raise an exception, then more work is required to duplicate its effects. Raising an exception would prevent the row from being inserted into the

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Direct Loads, Integrity Constraints, and Triggers table. To duplicate that effect with an update trigger, it is necessary to mark the loaded row for deletion.

The "new data" column cannot be used as a delete flag, because an update trigger cannot modify the columns that caused it to fire. So another column must be added to the table. This column marks the row for deletion. A null value means the row is valid. Whenever the insert trigger would raise an exception, the update trigger can mark the row as invalid by setting a flag in the additional column.

In summary, when an insert trigger can raise an exception condition, its effects can be duplicated by an update trigger, provided:

■

■

Two columns (which are usually null) are added to the table

The table can be updated exclusively (if necessary)

Using a Stored Procedure

The following procedure always works, but it is more complex to implement. It can be used when the insert trigger raises exceptions. It does not require a second additional column; and, because it does not replace the update trigger, it can be used without exclusive access to the table.

1.

2.

3.

4.

5.

Do the following to create a stored procedure that duplicates the effects of the insert trigger:

a.

Declare a cursor for the table, selecting all new rows.

b.

c.

d.

e.

Open the cursor and fetch rows, one at a time, in a processing loop.

Perform the operations contained in the insert trigger.

If the operations succeed, change the "new data" flag to null.

If the operations fail, change the "new data" flag to "bad data."

Execute the stored procedure using an administration tool such as SQL*Plus.

After running the procedure, check the table for any rows marked "bad data."

Update or remove the bad rows.

Reenable the insert trigger.

See Also:

PL/SQL User’s Guide and Reference for more information about cursor management

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Parallel Data Loading Models

Permanently Disabled Triggers and Constraints

SQL*Loader needs to acquire several locks on the table to be loaded to disable triggers and constraints. If a competing process is enabling triggers or constraints at the same time that SQL*Loader is trying to disable them for that table, then

SQL*Loader may not be able to acquire exclusive access to the table.

SQL*Loader attempts to handle this situation as gracefully as possible. It attempts to reenable disabled triggers and constraints before exiting. However, the same table-locking problem that made it impossible for SQL*Loader to continue may also have made it impossible for SQL*Loader to finish enabling triggers and constraints.

In such cases, triggers and constraints will remain disabled until they are manually enabled.

Although such a situation is unlikely, it is possible. The best way to prevent it is to make sure that no applications are running that could enable triggers or constraints for the table while the direct load is in progress.

If a direct load is aborted due to failure to acquire the proper locks, carefully check the log. It will show every trigger and constraint that was disabled, and each attempt to reenable them. Any triggers or constraints that were not reenabled by

SQL*Loader should be manually enabled with the ENABLE clause of the ALTER

TABLE

statement described in Oracle9i SQL Reference.

Increasing Performance with Concurrent Conventional Path Loads

If triggers or integrity constraints pose a problem, but you want faster loading, you should consider using concurrent conventional path loads. That is, use multiple load sessions executing concurrently on a multiple-CPU system. Split the input datafiles into separate files on logical record boundaries, and then load each such input datafile with a conventional path load session. The resulting load has the following attributes:

■

It is faster than a single conventional load on a multiple-CPU system, but probably not as fast as a direct load.

■

Triggers fire, integrity constraints are applied to the loaded rows, and indexes are maintained using the standard DML execution logic.

Parallel Data Loading Models

This section discusses three basic models of concurrency that you can use to minimize the elapsed time required for data loading:

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■

■

■

Concurrent conventional path loads

Intersegment concurrency with the direct path load method

Intrasegment concurrency with the direct path load method

Concurrent Conventional Path Loads

Using multiple conventional path load sessions executing concurrently is discussed in Increasing Performance with Concurrent Conventional Path Loads on page 9-30.

You can use this technique to load the same or different objects concurrently with no restrictions.

Intersegment Concurrency with Direct Path

Intersegment concurrency can be used for concurrent loading of different objects.

You can apply this technique to concurrent direct path loading of different tables, or to concurrent direct path loading of different partitions of the same table.

When you direct path load a single partition, consider the following items:

■

■

Local indexes can be maintained by the load.

Global indexes cannot be maintained by the load.

■

■

■

Referential integrity and CHECK constraints must be disabled.

Triggers must be disabled.

The input data should be partitioned (otherwise many records will be rejected, which adversely affects performance).

Intrasegment Concurrency with Direct Path

SQL*Loader permits multiple, concurrent sessions to perform a direct path load into the same table, or into the same partition of a partitioned table. Multiple

SQL*Loader sessions improve the performance of a direct path load given the available resources on your system.

This method of data loading is enabled by setting both the DIRECT and the

PARALLEL

parameters to true, and is often referred to as a parallel direct path load.

It is important to realize that parallelism is user managed. Setting the PARALLEL parameter to true only allows multiple concurrent direct path load sessions.

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Parallel Data Loading Models

Restrictions on Parallel Direct Path Loads

The following restrictions are enforced on parallel direct path loads:

■

■

■

Neither local or global indexes can be maintained by the load.

Referential integrity and CHECK constraints must be disabled.

Triggers must be disabled.

■

Rows can only be appended. REPLACE, TRUNCATE, and INSERT cannot be used

(this is due to the individual loads not being coordinated). If you must truncate a table before a parallel load, you must do it manually.

If a parallel direct path load is being applied to a single partition, you should partition the data first (otherwise, the overhead of record rejection due to a partition mismatch slows down the load).

Initiating Multiple SQL*Loader Sessions

Each SQL*Loader session takes a different datafile as input. In all sessions executing a direct load on the same table, you must set PARALLEL to true. The syntax is:

PARALLEL =

TRUE

FALSE

PARALLEL

can be specified on the command line or in a parameter file. It can also be specified in the control file with the OPTIONS clause.

For example, to invoke three SQL*Loader direct path load sessions on the same table, you would execute the following commands at the operating system prompt: sqlldr USERID=scott/tiger CONTROL=load1.ctl DIRECT=TRUE PARALLEL=true sqlldr USERID=scott/tiger CONTROL=load2.ctl DIRECT=TRUE PARALLEL=true sqlldr USERID=scott/tiger CONTROL=load3.ctl DIRECT=TRUE PARALLEL=true

The previous commands must be executed in separate sessions, or if permitted on your operating system, as separate background jobs. Note the use of multiple control files. This allows you to be flexible in specifying the files to use for the direct path load.

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Note:

Indexes are not maintained during a parallel load. Any indexes must be created or re-created manually after the load completes. You can use the parallel index creation or parallel index rebuild feature to speed the building of large indexes after a parallel load.

When you perform a parallel load, SQL*Loader creates temporary segments for each concurrent session and then merges the segments upon completion. The segment created from the merge is then added to the existing segment in the database above the segment’s high-water mark. The last extent used of each segment for each loader session is trimmed of any free space before being combined with the other extents of the SQL*Loader session.

Parameters for Parallel Direct Path Loads

When you perform parallel direct path loads, there are options available for specifying attributes of the temporary segment to be allocated by the loader.

Specifying Temporary Segments

To allow for maximum I/O throughput, Oracle Corporation recommends that each concurrent direct path load session use files located on different disks. Use the FILE parameter of the OPTIONS clause to specify the filename of any valid datafile in the tablespace of the object (table or partition) being loaded.

For example:

LOAD DATA

INFILE ’load1.dat’

INSERT INTO TABLE emp

OPTIONS(FILE=’/dat/data1.dat’)

(empno POSITION(01:04) INTEGER EXTERNAL NULLIF empno=BLANKS

...

You could also specify the FILE parameter on the command line of each concurrent

SQL*Loader session, but then it would apply globally to all objects being loaded with that session.

Using the FILE Parameter

The FILE parameter in the Oracle database server has the following restrictions for parallel direct path loads:

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Parallel Data Loading Models

■

■

■

For nonpartitioned tables:

The specified file must be in the tablespace of the table being loaded.

For partitioned tables, single-partition load:

The specified file must be in the tablespace of the partition being loaded.

For partitioned tables, full-table load:

The specified file must be in the tablespace of all partitions being loaded; that is, all partitions must be in the same tablespace.

Using the STORAGE Parameter

You can use the STORAGE parameter to specify the storage attributes of the temporary segments allocated for a parallel direct path load. If the STORAGE parameter is not used, the storage attributes of the segment containing the object (table, partition) being loaded are used. Also, when the

STORAGE

parameter is not specified, SQL*Loader uses a default of 2 KB for

EXTENTS.

OPTIONS(STORAGE=(MINEXTENTS n1 MAXEXTENTS n2 INITIAL n3[K|M]

NEXT n4[K|M] PCTINCREASE n5)

For example, the following STORAGE clause could be used:

OPTIONS (STORAGE=(INITIAL 100M NEXT 100M PCTINCREASE 0))

You can use the STORAGE parameter only in the control file, and not on the command line. Use of the STORAGE parameter to specify anything other than

PCTINCREASE of 0, and INITIAL or NEXT values is strongly discouraged (and may be silently ignored in the future).

Enabling Constraints After a Parallel Direct Path Load

Constraints and triggers must be enabled manually after all data loading is complete.

Because each SQL*Loader session can attempt to reenable constraints on a table after a direct path load, there is a danger that one session may attempt to reenable a constraint before another session is finished loading data. In this case, the first session to complete the load will be unable to enable the constraint because the remaining sessions possess share locks on the table.

Because there is a danger that some constraints might not be reenabled after a direct path load, you should check the status of the constraint after completing the load to ensure that it was enabled properly.

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General Performance Improvement Hints

PRIMARY KEY and UNIQUE KEY Constraints

PRIMARY KEY

and UNIQUE KEY constraints create indexes on a table when they are enabled, and subsequently can take a significantly long time to enable after a direct path loading session if the table is very large. You should consider enabling these constraints manually after a load (and not specifying the automatic enable feature).

This allows you to manually create the required indexes in parallel to save time before enabling the constraint.

See Also:

Oracle9i Database Performance Guide and Reference

General Performance Improvement Hints

If you have control over the format of the data to be loaded, you can use the following hints to improve load performance:

■

Make logical record processing efficient.

■

■

–

Use one-to-one mapping of physical records to logical records (avoid continueif, concatenate).

–

Make it easy for the software to identify physical record boundaries. Use the file processing option string "FIX nnn" or "VAR". If you use the default (stream mode) on most platforms (for example, UNIX and NT) the loader must scan each physical record for the record terminator (newline character).

Make field setting efficient. Field setting is the process of mapping fields in the datafile to their corresponding columns in the table being loaded. The mapping function is controlled by the description of the fields in the control file. Field setting (along with data conversion) is the biggest consumer of CPU cycles for most loads.

–

Avoid delimited fields; use positional fields. If you use delimited fields, the loader must scan the input data to find the delimiters. If you use positional fields, field setting becomes simple pointer arithmetic (very fast).

–

Do not trim whitespace if you do not need to (use PRESERVE BLANKS).

Make conversions efficient. SQL*Loader performs character set conversion and datatype conversion for you. Of course, the quickest conversion is no conversion.

–

Use single-byte character sets if you can.

Conventional and Direct Path Loads

9-35

General Performance Improvement Hints

–

Avoid character set conversions if you can. The loader supports four character sets:

*

Client character set (NLS_LANG of the client sqlldr process)

*

Datafile character set (usually the same as the client character set)

■

■

*

Database server character set

*

Database server national character set

Performance is optimized if all character sets are the same. For direct path loads, it is best if the datafile character set and the database server character set are the same. If the character sets are the same, character set conversion buffers are not allocated.

Use direct path loads.

Use the SORTED INDEXES clause.

■

■

Avoid unnecessary NULLIF and DEFAULTIF clauses. Each clause must be evaluated on each column that has a clause associated with it for every row loaded.

Use parallel direct path loads and parallel index creation when you can.

■

Be aware of the effect on performance when you have large values for both the

CONCATENATE

clause and the COLUMNARRAYROWS clause. See Using

CONCATENATE to Assemble Logical Records on page 5-27.

Additionally, the performance tips provided in Performance Hints When Using

External Tables on page 11-6 also apply to SQL*Loader.

9-36

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10

SQL*Loader Case Studies

The case studies in this chapter illustrate some of the features of SQL*Loader. These case studies start simply and progress in complexity.

Note:

The commands used in this chapter, such as sqlldr, are

UNIX-specific invocations. Refer to your Oracle operating system-specific documentation for information about the correct commands to use on your operating system.

This chapter contains the following sections:

■

The Case Studies

■

■

Case Study Files

Tables Used in the Case Studies

■

■

■

■

Checking the Results of a Load

References and Notes

Case Study 1: Loading Variable-Length Data

Case Study 2: Loading Fixed-Format Fields

■

■

■

■

■

Case Study 3: Loading a Delimited, Free-Format File

Case Study 4: Loading Combined Physical Records

Case Study 5: Loading Data into Multiple Tables

Case Study 6: Loading Data Using the Direct Path Load Method

Case Study 7: Extracting Data from a Formatted Report

SQL*Loader Case Studies

10-1

The Case Studies

■

■

■

■

Case Study 8: Loading Partitioned Tables

Case Study 9: Loading LOBFILEs (CLOBs)

Case Study 10: Loading REF Fields and VARRAYs

Case Study 11: Loading Data in the Unicode Character Set

The Case Studies

This chapter contains the following case studies:

■

■

■

■

■

■

■

■

■

■

Case Study 1: Loading Variable-Length Data on page 10-5: Loads stream format records in which the fields are terminated by commas and may be enclosed by quotation marks. The data is found at the end of the control file.

Case Study 2: Loading Fixed-Format Fields on page 10-8: Loads data from a separate datafile.

Case Study 3: Loading a Delimited, Free-Format File on page 10-11: Loads data from stream format records with delimited fields and sequence numbers. The data is found at the end of the control file.

Case Study 4: Loading Combined Physical Records on page 10-14: Combines multiple physical records into one logical record corresponding to one database row.

Case Study 5: Loading Data into Multiple Tables on page 10-18: Loads data into multiple tables in one run.

Case Study 6: Loading Data Using the Direct Path Load Method on page 10-24:

Loads data using the direct path load method.

Case Study 7: Extracting Data from a Formatted Report on page 10-28: Extracts data from a formatted report.

Case Study 8: Loading Partitioned Tables on page 10-34: Loads partitioned tables.

Case Study 9: Loading LOBFILEs (CLOBs) on page 10-38: Adds a CLOB column called resume to the table emp, uses a FILLER field (res_file), and loads multiple LOBFILEs into the emp table.

Case Study 10: Loading REF Fields and VARRAYs on page 10-43: Loads a customer table that has a primary key as its OID and stores order items in a

VARRAY

. Loads an order table that has a reference to the customer table and the order items in a VARRAY.

10-2

Oracle9 i

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Case Study Files

■

Case Study 11: Loading Data in the Unicode Character Set on page 10-47: Loads data in the Unicode character set, UTF16, in little endian byte order. This case study uses character-length semantics.

Case Study Files

The distribution media for SQL*Loader contains files for each case:

■

■

Control files (for example, ulcase5.ctl)

Datafiles (for example, ulcase5.dat)

■

Setup files (for example, ulcase5.sql)

If the sample data for the case study is contained in the control file, then there will be no .dat file for that case.

If there are no special setup steps for a case study, there may be no .sql file for that case. Starting (setup) and ending (cleanup) scripts are denoted by an S or E after the case number.

Table 10–1 lists the files associated with each case.

Table 10–1 Case Studies and Their Related Files

Case

5

6

7

3

4

1

2

8

9

10

11

.ctl

Yes

Yes

Yes

Yes

Yes

Yes

Yes

Yes

Yes

Yes

Yes

.dat

No

Yes

No

Yes

Yes

Yes

Yes

Yes

Yes

No

Yes

.sql

Yes

Yes

Yes

Yes

Yes

No

Yes

Yes

Yes

Yes

Yes (S, E)

SQL*Loader Case Studies

10-3

Tables Used in the Case Studies

Note:

The actual names of the case study files are operating system-dependent. See your Oracle operating system-specific documentation for the exact names.

Tables Used in the Case Studies

The case studies are based upon the standard Oracle demonstration database tables, emp and dept, owned by scott/tiger. (In some case studies, additional columns have been added.)

Contents of Table emp

(empno NUMBER(4) NOT NULL,

ename VARCHAR2(10),

job VARCHAR2(9),

mgr NUMBER(4),

hiredate DATE,

sal NUMBER(7,2),

comm NUMBER(7,2),

deptno NUMBER(2))

Contents of Table dept

(deptno NUMBER(2) NOT NULL,

dname VARCHAR2(14),

loc VARCHAR2(13))

Checking the Results of a Load

To check the results of a load, start SQL*Plus and perform a select operation from the table that was loaded in the case study. This is done, as follows:

1.

Start SQL*Plus as scott/tiger by entering the following at the system prompt: sqlplus scott/tiger

2.

The SQL prompt is displayed.

At the SQL prompt, use the SELECT statement to select all rows from the table that the case study loaded. For example, if the table emp was loaded, enter:

SQL> SELECT * FROM emp;

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Oracle9 i

Database Utilities

Case Study 1: Loading Variable-Length Data

The contents of each row in the emp table will be displayed.

References and Notes

The summary at the beginning of each case study directs you to the sections of this guide that discuss the SQL*Loader feature being demonstrated.

In the control file fragment and log file listing shown for each case study, the numbers that appear to the left are not actually in the file; they are keyed to the numbered notes following the listing. Do not use these numbers when you write your control files.

Case Study 1: Loading Variable-Length Data

Case 1 demonstrates:

■

■

■

A simple control file identifying one table and three columns to be loaded.

Including data to be loaded from the control file itself, so there is no separate datafile. See Identifying Data in the Control File with BEGINDATA on page 5-10.

Loading data in stream format, with both types of delimited fields: terminated and enclosed. See Field Length Specifications for Datatypes for Which

Whitespace Can Be Trimmed on page 6-45.

Control File for Case Study 1

The control file is ulcase1.ctl:

1)

LOAD DATA

2)

INFILE *

3)

INTO TABLE dept

4)

FIELDS TERMINATED BY ’,’ OPTIONALLY ENCLOSED BY ’"’

5)

(deptno, dname, loc)

6)

BEGINDATA

12,RESEARCH,"SARATOGA"

10,"ACCOUNTING",CLEVELAND

11,"ART",SALEM

13,FINANCE,"BOSTON"

21,"SALES",PHILA.

22,"SALES",ROCHESTER

42,"INT’L","SAN FRAN"

SQL*Loader Case Studies

10-5

Case Study 1: Loading Variable-Length Data

Notes:

1.

2.

3.

4.

5.

6.

The LOAD DATA statement is required at the beginning of the control file.

INFILE *

specifies that the data is found in the control file and not in an external file.

The INTO TABLE statement is required to identify the table to be loaded (dept) into. By default, SQL*Loader requires the table to be empty before it inserts any records.

FIELDS TERMINATED BY

specifies that the data is terminated by commas, but may also be enclosed by quotation marks. Datatypes for all fields default to

CHAR

.

The names of columns to load are enclosed in parentheses. Because no datatype or length is specified, the default is type CHAR with a maximum length of 255.

BEGINDATA

specifies the beginning of the data.

Running Case Study 1

Take the following steps to run the case study.

1.

Start SQL*Plus as scott/tiger by entering the following at the system prompt: sqlplus scott/tiger

2.

The SQL prompt is displayed.

At the SQL prompt, execute the SQL script for this case study, as follows:

SQL> @ulcase1

3.

This prepares and populates tables for the case study and then returns you to the system prompt.

At the system prompt, invoke SQL*Loader and run the case study, as follows: sqlldr USERID=scott/tiger CONTROL=ulcase1.ctl LOG=ulcase1.log

SQL*Loader loads the dept table, creates the log file, and returns you to the system prompt. You can check the log file to see the results of running the case study.

10-6

Oracle9 i

Database Utilities

Case Study 1: Loading Variable-Length Data

Log File for Case Study 1

The following shows a portion of the log file:

Control File: ulcase1.ctl

Data File: ulcase1.ctl

Bad File: ulcase1.bad

Discard File: none specified

(Allow all discards)

Number to load: ALL

Number to skip: 0

Errors allowed: 50

Bind array: 64 rows, maximum of 256000 bytes

Continuation: none specified

Path used: Conventional

Table DEPT, loaded from every logical record.

Insert option in effect for this table: INSERT

Column Name Position Len Term Encl Datatype

------------------------------ ---------- ----- ---- ---- ---------------------

1)

DEPTNO FIRST * , O(") CHARACTER

DNAME

2)

LOC

NEXT

NEXT

*

*

,

,

O(") CHARACTER

O(") CHARACTER

Table DEPT:

7 Rows successfully loaded.

0 Rows not loaded due to data errors.

0 Rows not loaded because all WHEN clauses were failed.

0 Rows not loaded because all fields were null.

Space allocated for bind array: 49536 bytes(64 rows)

Read buffer bytes: 1048576

Total logical records skipped: 0

Total logical records read: 7

Total logical records rejected: 0

Total logical records discarded: 0

Run began on Wed Feb 27 14:10:13 2002

Run ended on Wed Feb 27 14:10:14 2002

SQL*Loader Case Studies

10-7

Case Study 2: Loading Fixed-Format Fields

Elapsed time was: 00:00:01.53

CPU time was: 00:00:00.20

Notes:

1.

2.

Position and length for each field are determined for each record, based on delimiters in the input file.

The notation O(") signifies optional enclosure by quotation marks.

Case Study 2: Loading Fixed-Format Fields

Case 2 demonstrates:

■

A separate datafile. See Specifying Datafiles on page 5-7.

■

Data conversions. See Datatype Conversions on page 6-22.

In this case, the field positions and datatypes are specified explicitly.

Control File for Case Study 2

The control file is ulcase2.ctl.

1)

LOAD DATA

2)

INFILE ’ulcase2.dat’

3)

INTO TABLE emp

4)

(empno POSITION(01:04) INTEGER EXTERNAL,

ename POSITION(06:15) CHAR,

job POSITION(17:25) CHAR,

mgr POSITION(27:30) INTEGER EXTERNAL,

sal POSITION(32:39) DECIMAL EXTERNAL,

comm POSITION(41:48) DECIMAL EXTERNAL,

5)

deptno POSITION(50:51) INTEGER EXTERNAL)

Notes:

1.

The LOAD DATA statement is required at the beginning of the control file.

2.

3.

4.

The name of the file containing data follows the INFILE parameter.

The INTO TABLE statement is required to identify the table to be loaded into.

Lines 4 and 5 identify a column name and the location of the data in the datafile to be loaded into that column. empno, ename, job, and so on are names of columns in table emp. The datatypes (INTEGER EXTERNAL, CHAR, DECIMAL

10-8

Oracle9 i

Database Utilities

Case Study 2: Loading Fixed-Format Fields

5.

EXTERNAL

) identify the datatype of data fields in the file, not of corresponding columns in the emp table.

Note that the set of column specifications is enclosed in parentheses.

Datafile for Case Study 2

The following are a few sample data lines from the file ulcase2.dat. Blank fields are set to null automatically.

7782 CLARK MANAGER 7839 2572.50 10

7839 KING PRESIDENT 5500.00 10

7934 MILLER CLERK 7782 920.00 10

7566 JONES MANAGER 7839 3123.75 20

7499 ALLEN SALESMAN 7698 1600.00 300.00 30

7654 MARTIN SALESMAN 7698 1312.50 1400.00 30

7658 CHAN ANALYST 7566 3450.00 20

7654 MARTIN SALESMAN 7698 1312.50 1400.00 30

Running Case Study 2

Take the following steps to run the case study. If you have already run case study 1, you can skip to step 3 because the ulcase1.sql script handles both case 1 and case

2.

1.

Start SQL*Plus as scott/tiger by entering the following at the system prompt: sqlplus scott/tiger

2.

The SQL prompt is displayed.

At the SQL prompt, execute the SQL script for this case study, as follows:

SQL> @ulcase1

3.

This prepares and populates tables for the case study and then returns you to the system prompt.

At the system prompt, invoke SQL*Loader and run the case study, as follows: sqlldr USERID=scott/tiger CONTROL=ulcase2.ctl LOG=ulcase2.log

SQL*Loader loads the table, creates the log file, and returns you to the system prompt. You can check the log file to see the results of running the case study.

SQL*Loader Case Studies

10-9

Case Study 2: Loading Fixed-Format Fields

Records loaded in this example from the emp table contain department numbers. Unless the dept table is loaded first, referential integrity checking rejects these records (if referential integrity constraints are enabled for the emp table).

Log File for Case Study 2

The following shows a portion of the log file:

Control File: ulcase2.ctl

Data File: ulcase2.dat

Bad File: ulcase2.bad

Discard File: none specified

(Allow all discards)

Number to load: ALL

Number to skip: 0

Errors allowed: 50

Bind array: 64 rows, maximum of 256000 bytes

Continuation: none specified

Path used: Conventional

Table EMP, loaded from every logical record.

Insert option in effect for this table: INSERT

Column Name Position Len Term Encl Datatype

------------------------------ ---------- ----- ---- ---- ---------------------

EMPNO 1:4 4 CHARACTER

ENAME 6:15 10 CHARACTER

JOB 17:25 9 CHARACTER

MGR 27:30 4 CHARACTER

SAL 32:39 8 CHARACTER

COMM 41:48 8 CHARACTER

DEPTNO 50:51 2 CHARACTER

Table EMP:

7 Rows successfully loaded.

0 Rows not loaded due to data errors.

0 Rows not loaded because all WHEN clauses were failed.

0 Rows not loaded because all fields were null.

Space allocated for bind array: 3840 bytes(64 rows)

10-10

Oracle9 i

Database Utilities

Case Study 3: Loading a Delimited, Free-Format File

Read buffer bytes: 1048576

Total logical records skipped: 0

Total logical records read: 7

Total logical records rejected: 0

Total logical records discarded: 0

Run began on Wed Feb 27 14:17:39 2002

Run ended on Wed Feb 27 14:17:39 2002

Elapsed time was: 00:00:00.81

CPU time was: 00:00:00.15

Case Study 3: Loading a Delimited, Free-Format File

Case 3 demonstrates:

■

Loading data (enclosed and terminated) in stream format. See Delimited Fields on page 6-45.

■

■

■

■

Loading dates using the datatype DATE. See Datetime and Interval Datatypes on page 6-16.

Using SEQUENCE numbers to generate unique keys for loaded data. See Setting a Column to a Unique Sequence Number on page 6-57.

Using APPEND to indicate that the table need not be empty before inserting new records. See Table-Specific Loading Method on page 5-32.

Using Comments in the control file set off by two hyphens. See Comments in the Control File on page 5-4.

Control File for Case Study 3

This control file loads the same table as in case 2, but it loads three additional columns (hiredate, projno, and loadseq). The demonstration table emp does not have columns projno and loadseq. To test this control file, add these columns to the emp table with the command:

ALTER TABLE emp ADD (projno NUMBER, loadseq NUMBER);

The data is in a different format than in case 2. Some data is enclosed in quotation marks, some is set off by commas, and the values for deptno and projno are separated by a colon.

SQL*Loader Case Studies

10-11

Case Study 3: Loading a Delimited, Free-Format File

1)

-- Variable-length, delimited, and enclosed data format

LOAD DATA

2)

INFILE *

3)

APPEND

INTO TABLE emp

4)

FIELDS TERMINATED BY "," OPTIONALLY ENCLOSED BY ’"’

(empno, ename, job, mgr,

5)

hiredate DATE(20) "DD-Month-YYYY",

sal, comm, deptno CHAR TERMINATED BY ’:’,

projno,

6)

loadseq SEQUENCE(MAX,1))

7)

BEGINDATA

8)

7782, "Clark", "Manager", 7839, 09-June-1981, 2572.50,, 10:101

7839, "King", "President", , 17-November-1981,5500.00,,10:102

7934, "Miller", "Clerk", 7782, 23-January-1982, 920.00,, 10:102

7566, "Jones", "Manager", 7839, 02-April-1981, 3123.75,, 20:101

7499, "Allen", "Salesman", 7698, 20-February-1981, 1600.00,

(same line continued) 300.00, 30:103

7654, "Martin", "Salesman", 7698, 28-September-1981, 1312.50,

(same line continued) 1400.00, 3:103

7658, "Chan", "Analyst", 7566, 03-May-1982, 3450,, 20:101

Notes:

1.

Comments may appear anywhere in the command lines of the file, but they should not appear in data. They are preceded with two hyphens that may appear anywhere on a line.

2.

3.

INFILE *

specifies that the data is found at the end of the control file.

APPEND

specifies that the data can be loaded even if the table already contains rows. That is, the table need not be empty.

4.

5.

6.

The default terminator for the data fields is a comma, and some fields may be enclosed by double quotation marks (").

The data to be loaded into column hiredate appears in the format

DD-Month-YYYY. The length of the date field is specified to have a maximum of 20. The maximum length is in bytes, with default byte-length semantics. If character-length semantics were used instead, the length would be in characters. If a length is not specified, then the length depends on the length of the date mask.

The SEQUENCE function generates a unique value in the column loadseq. This function finds the current maximum value in column loadseq and adds the increment (1) to it to obtain the value for loadseq for each row inserted.

10-12

Oracle9 i

Database Utilities

Case Study 3: Loading a Delimited, Free-Format File

7.

8.

BEGINDATA

specifies the end of the control information and the beginning of the data.

Although each physical record equals one logical record, the fields vary in length, so that some records are longer than others. Note also that several rows have null values for comm.

Running Case Study 3

Take the following steps to run the case study.

1.

Start SQL*Plus as scott/tiger by entering the following at the system prompt: sqlplus scott/tiger

2.

The SQL prompt is displayed.

At the SQL prompt, execute the SQL script for this case study, as follows:

SQL> @ulcase3

3.

This prepares and populates tables for the case study and then returns you to the system prompt.

At the system prompt, invoke SQL*Loader and run the case study, as follows: sqlldr USERID=scott/tiger CONTROL=ulcase3.ctl LOG=ulcase3.log

SQL*Loader loads the table, creates the log file, and returns you to the system prompt. You can check the log file to see the results of running the case study.

Log File for Case Study 3

The following shows a portion of the log file:

Control File: ulcase3.ctl

Data File: ulcase3.ctl

Bad File: ulcase3.bad

Discard File: none specified

(Allow all discards)

Number to load: ALL

Number to skip: 0

Errors allowed: 50

Bind array: 64 rows, maximum of 256000 bytes

SQL*Loader Case Studies

10-13

Case Study 4: Loading Combined Physical Records

Continuation: none specified

Path used: Conventional

Table EMP, loaded from every logical record.

Insert option in effect for this table: APPEND

Column Name Position Len Term Encl Datatype

------------------------------ ---------- ----- ---- ---- ---------------------

EMPNO FIRST * , O(") CHARACTER

ENAME NEXT * , O(") CHARACTER

JOB NEXT * , O(") CHARACTER

MGR NEXT * , O(") CHARACTER

HIREDATE NEXT 20 , O(") DATE DD-Month-YYYY

SAL NEXT * , O(") CHARACTER

COMM NEXT * , O(") CHARACTER

DEPTNO NEXT * : O(") CHARACTER

PROJNO NEXT * , O(") CHARACTER

LOADSEQ SEQUENCE (MAX, 1)

Table EMP:

7 Rows successfully loaded.

0 Rows not loaded due to data errors.

0 Rows not loaded because all WHEN clauses were failed.

0 Rows not loaded because all fields were null.

Space allocated for bind array: 134976 bytes(64 rows)

Read buffer bytes: 1048576

Total logical records skipped: 0

Total logical records read: 7

Total logical records rejected: 0

Total logical records discarded: 0

Run began on Wed Feb 27 14:25:29 2002

Run ended on Wed Feb 27 14:25:30 2002

Elapsed time was: 00:00:00.81

CPU time was: 00:00:00.15

Case Study 4: Loading Combined Physical Records

Case 4 demonstrates:

10-14

Oracle9 i

Database Utilities

Case Study 4: Loading Combined Physical Records

■

■

■

■

■

■

Combining multiple physical records to form one logical record with

CONTINUEIF

; see Using CONTINUEIF to Assemble Logical Records on page 5-27.

Inserting negative numbers.

Indicating with REPLACE that the table should be emptied before the new data is inserted; see Table-Specific Loading Method on page 5-32.

Specifying a discard file in the control file using DISCARDFILE; see Specifying the Discard File on page 5-14.

Specifying a maximum number of discards using DISCARDMAX; see Specifying the Discard File on page 5-14.

Rejecting records due to duplicate values in a unique index or due to invalid data values; see Criteria for Rejected Records on page 5-13.

Control File for Case Study 4

The control file is ulcase4.ctl:

LOAD DATA

INFILE ’ulcase4.dat’

1)

DISCARDFILE ’ulcase4.dsc’

2)

DISCARDMAX 999

3)

REPLACE

4)

CONTINUEIF THIS (1) = ’*’

INTO TABLE emp

(empno POSITION(1:4) INTEGER EXTERNAL,

ename POSITION(6:15) CHAR,

job POSITION(17:25) CHAR,

mgr POSITION(27:30) INTEGER EXTERNAL,

sal POSITION(32:39) DECIMAL EXTERNAL,

comm POSITION(41:48) DECIMAL EXTERNAL,

deptno POSITION(50:51) INTEGER EXTERNAL,

hiredate POSITION(52:60) INTEGER EXTERNAL)

Notes:

1.

2.

3.

DISCARDFILE

specifies a discard file named ulcase4.dsc.

DISCARDMAX

specifies a maximum of 999 discards allowed before terminating the run (for all practical purposes, this allows all discards).

REPLACE

specifies that if there is data in the table being loaded, then

SQL*Loader should delete that data before loading new data.

SQL*Loader Case Studies

10-15

Case Study 4: Loading Combined Physical Records

4.

CONTINUEIF THIS

specifies that if an asterisk is found in column 1 of the current record, then the next physical record after that record should be appended to it from the logical record. Note that column 1 in each physical record should then contain either an asterisk or a nondata value.

Datafile for Case Study 4

The datafile for this case, ulcase4.dat, looks as follows. Asterisks are in the first position and, though not visible, a newline character is in position 20. Note that clark

’s commission is -10, and SQL*Loader loads the value, converting it to a negative number.

*7782 CLARK

MANAGER 7839 2572.50 -10 25 12-NOV-85

*7839 KING

PRESIDENT 5500.00 25 05-APR-83

*7934 MILLER

CLERK 7782 920.00 25 08-MAY-80

*7566 JONES

MANAGER 7839 3123.75 25 17-JUL-85

*7499 ALLEN

SALESMAN 7698 1600.00 300.00 25 3-JUN-84

*7654 MARTIN

SALESMAN 7698 1312.50 1400.00 25 21-DEC-85

*7658 CHAN

ANALYST 7566 3450.00 25 16-FEB-84

* CHEN

ANALYST 7566 3450.00 25 16-FEB-84

*7658 CHIN

ANALYST 7566 3450.00 25 16-FEB-84

Rejected Records

The last two records are rejected, given two assumptions. If a unique index is created on column empno, then the record for chin will be rejected because his empno

is identical to chan’s. If empno is defined as NOT NULL, then chen’s record will be rejected because it has no value for empno.

Running Case Study 4

Take the following steps to run the case study.

1.

Start SQL*Plus as scott/tiger by entering the following at the system prompt:

10-16

Oracle9 i

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Case Study 4: Loading Combined Physical Records sqlplus scott/tiger

2.

The SQL prompt is displayed.

At the SQL prompt, execute the SQL script for this case study, as follows:

SQL> @ulcase4

3.

This prepares and populates tables for the case study and then returns you to the system prompt.

At the system prompt, invoke SQL*Loader and run the case study, as follows: sqlldr USERID=scott/tiger CONTROL=ulcase4.ctl LOG=ulcase4.log

SQL*Loader loads the table, creates the log file, and returns you to the system prompt. You can check the log file to see the results of running the case study.

Log File for Case Study 4

The following is a portion of the log file:

Control File: ulcase4.ctl

Data File: ulcase4.dat

Bad File: ulcase4.bad

Discard File: ulcase4.dis

(Allow 999 discards)

Number to load: ALL

Number to skip: 0

Errors allowed: 50

Bind array: 64 rows, maximum of 256000 bytes

Continuation: 1:1 = 0X2a(character ’*’), in current physical record

Path used: Conventional

Table EMP, loaded from every logical record.

Insert option in effect for this table: REPLACE

Column Name Position Len Term Encl Datatype

------------------------------ ---------- ----- ---- ---- ---------------------

EMPNO 1:4 4 CHARACTER

ENAME 6:15 10 CHARACTER

JOB 17:25 9 CHARACTER

MGR 27:30 4 CHARACTER

SAL 32:39 8 CHARACTER

COMM 41:48 8 CHARACTER

SQL*Loader Case Studies

10-17

Case Study 5: Loading Data into Multiple Tables

DEPTNO 50:51 2 CHARACTER

HIREDATE 52:60 9 CHARACTER

Record 8: Rejected - Error on table EMP.

ORA-01400: cannot insert NULL into ("SCOTT"."EMP"."EMPNO")

Record 9: Rejected - Error on table EMP.

ORA-00001: unique constraint (SCOTT.EMPIX) violated

Table EMP:

7 Rows successfully loaded.

2 Rows not loaded due to data errors.

0 Rows not loaded because all WHEN clauses were failed.

0 Rows not loaded because all fields were null.

Space allocated for bind array: 4608 bytes(64 rows)

Read buffer bytes: 1048576

Total logical records skipped: 0

Total logical records read: 9

Total logical records rejected: 2

Total logical records discarded: 0

Run began on Wed Feb 27 14:28:53 2002

Run ended on Wed Feb 27 14:28:54 2002

Elapsed time was: 00:00:00.91

CPU time was: 00:00:00.13

Bad File for Case Study 4

The bad file, shown in the following display, lists records 8 and 9 for the reasons stated earlier. (The discard file is not created.)

* CHEN ANALYST

7566 3450.00 25 16-FEB-84

*7658 CHIN ANALYST

7566 3450.00 25 16-FEB-84

Case Study 5: Loading Data into Multiple Tables

Case 5 demonstrates:

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Case Study 5: Loading Data into Multiple Tables

■

■

■

■

■

Loading multiple tables. See Loading Data into Multiple Tables on page 5-43.

Using SQL*Loader to break down repeating groups in a flat file and to load the data into normalized tables. In this way, one file record may generate multiple database rows.

Deriving multiple logical records from each physical record. See Benefits of

Using Multiple INTO TABLE Clauses on page 5-39.

Using a WHEN clause. See Loading Records Based on a Condition on page 5-35.

Loading the same field (empno) into multiple tables.

Control File for Case Study 5

The control file is ulcase5.ctl.

-- Loads EMP records from first 23 characters

-- Creates and loads PROJ records for each PROJNO listed

-- for each employee

LOAD DATA

INFILE ’ulcase5.dat’

BADFILE ’ulcase5.bad’

DISCARDFILE ’ulcase5.dsc’

1)

REPLACE

2)

INTO TABLE emp

(empno POSITION(1:4) INTEGER EXTERNAL,

ename POSITION(6:15) CHAR,

deptno POSITION(17:18) CHAR,

mgr POSITION(20:23) INTEGER EXTERNAL)

2)

INTO TABLE proj

-- PROJ has two columns, both not null: EMPNO and PROJNO

3)

WHEN projno != ’ ’

(empno POSITION(1:4) INTEGER EXTERNAL,

3)

projno POSITION(25:27) INTEGER EXTERNAL) -- 1st proj

2)

INTO TABLE proj

4)

WHEN projno != ’ ’

(empno POSITION(1:4) INTEGER EXTERNAL,

4)

projno POSITION(29:31 INTEGER EXTERNAL) -- 2nd proj

2)

INTO TABLE proj

5)

WHEN projno != ’ ’

(empno POSITION(1:4) INTEGER EXTERNAL,

5)

projno POSITION(33:35) INTEGER EXTERNAL) -- 3rd proj

Notes:

SQL*Loader Case Studies

10-19

Case Study 5: Loading Data into Multiple Tables

1.

2.

3.

4.

5.

REPLACE

specifies that if there is data in the tables to be loaded (emp and proj

), SQL*loader should delete the data before loading new rows.

Multiple INTO TABLE clauses load two tables, emp and proj. The same set of records is processed three times, using different combinations of columns each time to load table proj.

WHEN

loads only rows with nonblank project numbers. When projno is defined as columns 25...27, rows are inserted into proj only if there is a value in those columns.

When projno is defined as columns 29...31, rows are inserted into proj only if there is a value in those columns.

When projno is defined as columns 33...35, rows are inserted into proj only if there is a value in those columns.

Datafile for Case Study 5

1234 BAKER 10 9999 101 102 103

1234 JOKER 10 9999 777 888 999

2664 YOUNG 20 2893 425 abc 102

5321 OTOOLE 10 9999 321 55 40

2134 FARMER 20 4555 236 456

2414 LITTLE 20 5634 236 456 40

6542 LEE 10 4532 102 321 14

2849 EDDS xx 4555 294 40

4532 PERKINS 10 9999 40

1244 HUNT 11 3452 665 133 456

123 DOOLITTLE 12 9940 132

1453 MACDONALD 25 5532 200

Running Case Study 5

Take the following steps to run the case study.

1.

Start SQL*Plus as scott/tiger by entering the following at the system prompt: sqlplus scott/tiger

2.

The SQL prompt is displayed.

At the SQL prompt, execute the SQL script for this case study, as follows:

SQL> @ulcase5

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Case Study 5: Loading Data into Multiple Tables

3.

This prepares and populates tables for the case study and then returns you to the system prompt.

At the system prompt, invoke SQL*Loader and run the case study, as follows: sqlldr USERID=scott/tiger CONTROL=ulcase5.ctl LOG=ulcase5.log

SQL*Loader loads the tables, creates the log file, and returns you to the system prompt. You can check the log file to see the results of running the case study.

Log File for Case Study 5

The following is a portion of the log file:

Control File: ulcase5.ctl

Data File: ulcase5.dat

Bad File: ulcase5.bad

Discard File: ulcase5.dis

(Allow all discards)

Number to load: ALL

Number to skip: 0

Errors allowed: 50

Bind array: 64 rows, maximum of 256000 bytes

Continuation: none specified

Path used: Conventional

Table EMP, loaded from every logical record.

Insert option in effect for this table: REPLACE

Column Name Position Len Term Encl Datatype

------------------------------ ---------- ----- ---- ---- ---------------------

EMPNO 1:4 4 CHARACTER

ENAME 6:15 10 CHARACTER

DEPTNO 17:18 2 CHARACTER

MGR 20:23 4 CHARACTER

Table PROJ, loaded when PROJNO != 0X202020(character ’ ’)

Insert option in effect for this table: REPLACE

Column Name Position Len Term Encl Datatype

------------------------------ ---------- ----- ---- ---- ---------------------

EMPNO 1:4 4 CHARACTER

PROJNO 25:27 3 CHARACTER

SQL*Loader Case Studies

10-21

Case Study 5: Loading Data into Multiple Tables

Table PROJ, loaded when PROJNO != 0X202020(character ’ ’)

Insert option in effect for this table: REPLACE

Column Name Position Len Term Encl Datatype

------------------------------ ---------- ----- ---- ---- ---------------------

EMPNO 1:4 4 CHARACTER

PROJNO 29:31 3 CHARACTER

Table PROJ, loaded when PROJNO != 0X202020(character ’ ’)

Insert option in effect for this table: REPLACE

Column Name Position Len Term Encl Datatype

------------------------------ ---------- ----- ---- ---- ---------------------

EMPNO 1:4 4 CHARACTER

PROJNO 33:35 3 CHARACTER

1)

Record 2: Rejected - Error on table EMP.

1)

ORA-00001: unique constraint (SCOTT.EMPIX) violated

1)

Record 8: Rejected - Error on table EMP, column DEPTNO.

1)

ORA-01722: invalid number

1)

Record 3: Rejected - Error on table PROJ, column PROJNO.

1)

ORA-01722: invalid number

Table EMP:

2)

9 Rows successfully loaded.

2)

3 Rows not loaded due to data errors.

2)

0 Rows not loaded because all WHEN clauses were failed.

2)

0 Rows not loaded because all fields were null.

Table PROJ:

3)

7 Rows successfully loaded.

3)

2 Rows not loaded due to data errors.

3)

3 Rows not loaded because all WHEN clauses were failed.

3)

0 Rows not loaded because all fields were null.

Table PROJ:

4)

7 Rows successfully loaded.

4)

3 Rows not loaded due to data errors.

4)

2 Rows not loaded because all WHEN clauses were failed.

4)

0 Rows not loaded because all fields were null.

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Case Study 5: Loading Data into Multiple Tables

Table PROJ:

5)

6 Rows successfully loaded.

5)

3 Rows not loaded due to data errors.

5)

3 Rows not loaded because all WHEN clauses were failed.

5)

0 Rows not loaded because all fields were null.

Space allocated for bind array: 4096 bytes(64 rows)

Read buffer bytes: 1048576

Total logical records skipped: 0

Total logical records read: 12

Total logical records rejected: 3

Total logical records discarded: 0

Run began on Wed Feb 27 14:34:33 2002

Run ended on Wed Feb 27 14:34:34 2002

Elapsed time was: 00:00:01.00

CPU time was: 00:00:00.22

Notes:

1.

Errors are not encountered in the same order as the physical records due to buffering (array batch). The bad file and discard file contain records in the same order as they appear in the log file.

2.

3.

4.

5.

Of the 12 logical records for input, three rows were rejected (rows for joker, young

, and edds). No data was loaded for any of the rejected records.

Of the 9 records that met the WHEN clause criteria, two (joker and young) were rejected due to data errors.

Of the 10 records that met the WHEN clause criteria, three (joker, young, and edds

) were rejected due to data errors.

Of the 9 records that met the WHEN clause criteria, three (joker, young, and edds

) were rejected due to data errors.

Loaded Tables for Case Study 5

The following are sample SQL queries and their results:

SQL> SELECT empno, ename, mgr, deptno FROM emp;

SQL*Loader Case Studies

10-23

Case Study 6: Loading Data Using the Direct Path Load Method

EMPNO ENAME MGR DEPTNO

------ ------ ------ ------

1234 BAKER 9999 10

5321 OTOOLE 9999 10

2134 FARMER 4555 20

2414 LITTLE 5634 20

6542 LEE 4532 10

4532 PERKINS 9999 10

1244 HUNT 3452 11

123 DOOLITTLE 9940 12

1453 MACDONALD 5532 25

SQL> SELECT * from PROJ order by EMPNO;

EMPNO PROJNO

------ ------

123 132

1234 101

1234 103

1234 102

1244 665

1244 456

1244 133

1453 200

2134 236

2134 456

2414 236

2414 456

2414 40

4532 40

5321 321

5321 40

5321 55

6542 102

6542 14

6542 321

Case Study 6: Loading Data Using the Direct Path Load Method

This case study loads the emp table using the direct path load method and concurrently builds all indexes. It illustrates the following functions:

■

Use of the direct path load method to load and index data. See Chapter 9 .

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Case Study 6: Loading Data Using the Direct Path Load Method

■

■

■

How to specify the indexes for which the data is presorted. See Presorting Data for Faster Indexing on page 9-18.

The NULLIF clause. See Using the WHEN, NULLIF, and DEFAULTIF Clauses on page 6-32.

Loading all-blank numeric fields as NULL. See Loading All-Blank Fields on page 6-41.

In this example, field positions and datatypes are specified explicitly.

Control File for Case Study 6

The control file is ulcase6.ctl.

LOAD DATA

INFILE ’ulcase6.dat’

REPLACE

INTO TABLE emp

1)

SORTED INDEXES (empix)

2)

(empno POSITION(01:04) INTEGER EXTERNAL NULLIF empno=BLANKS,

ename POSITION(06:15) CHAR,

job POSITION(17:25) CHAR,

mgr POSITION(27:30) INTEGER EXTERNAL NULLIF mgr=BLANKS,

sal POSITION(32:39) DECIMAL EXTERNAL NULLIF sal=BLANKS,

comm POSITION(41:48) DECIMAL EXTERNAL NULLIF comm=BLANKS,

deptno POSITION(50:51) INTEGER EXTERNAL NULLIF deptno=BLANKS)

Notes:

1.

2.

The SORTED INDEXES statement identifies the indexes on which the data is sorted. This statement indicates that the datafile is sorted on the columns in the empix

index. It allows SQL*Loader to optimize index creation by eliminating the sort phase for this data when using the direct path load method.

The NULLIF...BLANKS clause specifies that the column should be loaded as

NULL

if the field in the datafile consists of all blanks. For more information, refer to Using the WHEN, NULLIF, and DEFAULTIF Clauses on page 6-32.

Datafile for Case Study 6

7499 ALLEN SALESMAN 7698 1600.00 300.00 30

7566 JONES MANAGER 7839 3123.75 20

7654 MARTIN SALESMAN 7698 1312.50 1400.00 30

7658 CHAN ANALYST 7566 3450.00 20

7782 CLARK MANAGER 7839 2572.50 10

SQL*Loader Case Studies

10-25

Case Study 6: Loading Data Using the Direct Path Load Method

7839 KING PRESIDENT 5500.00 10

7934 MILLER CLERK 7782 920.00 10

Running Case Study 6

Take the following steps to run the case study.

1.

Start SQL*Plus as scott/tiger by entering the following at the system prompt: sqlplus scott/tiger

2.

The SQL prompt is displayed.

At the SQL prompt, execute the SQL script for this case study, as follows:

SQL> @ulcase6

3.

This prepares and populates tables for the case study and then returns you to the system prompt.

At the system prompt, invoke SQL*Loader and run the case study, as follows.

Be sure to specify DIRECT=true.Otherwise, conventional path is used as the default, which will result in failure of the case study.

sqlldr USERID=scott/tiger CONTROL=ulcase6.ctl LOG=ulcase6.log DIRECT=true

SQL*Loader loads the emp table using the direct path load method, creates the log file, and returns you to the system prompt. You can check the log file to see the results of running the case study.

Log File for Case Study 6

The following is a portion of the log file:

Control File: ulcase6.ctl

Data File: ulcase6.dat

Bad File: ulcase6.bad

Discard File: none specified

(Allow all discards)

Number to load: ALL

Number to skip: 0

Errors allowed: 50

Continuation: none specified

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Case Study 6: Loading Data Using the Direct Path Load Method

Path used: Direct

Table EMP, loaded from every logical record.

Insert option in effect for this table: REPLACE

Column Name Position Len Term Encl Datatype

------------------------------ ---------- ----- ---- ---- ---------------------

EMPNO 1:4 4 CHARACTER

ENAME 6:15 10 CHARACTER

JOB 17:25 9 CHARACTER

MGR 27:30 4 CHARACTER

NULL if MGR = BLANKS

SAL 32:39 8 CHARACTER

NULL if SAL = BLANKS

COMM 41:48 8 CHARACTER

NULL if COMM = BLANKS

DEPTNO 50:51 2 CHARACTER

NULL if EMPNO = BLANKS

The following index(es) on table EMP were processed: index SCOTT.EMPIX loaded successfully with 7 keys

Table EMP:

7 Rows successfully loaded.

0 Rows not loaded due to data errors.

0 Rows not loaded because all WHEN clauses were failed.

0 Rows not loaded because all fields were null.

Bind array size not used in direct path.

Column array rows : 5000

Stream buffer bytes: 256000

Read buffer bytes: 1048576

Total logical records skipped: 0

Total logical records read: 7

Total logical records rejected: 0

Total logical records discarded: 0

Total stream buffers loaded by SQL*Loader main thread: 2

Total stream buffers loaded by SQL*Loader load thread: 0

Run began on Wed Feb 27 13:21:29 2002

Run ended on Wed Feb 27 13:21:32 2002

Elapsed time was: 00:00:02.96

CPU time was: 00:00:00.22

SQL*Loader Case Studies

10-27

Case Study 7: Extracting Data from a Formatted Report

Case Study 7: Extracting Data from a Formatted Report

In this case study, SQL*Loader string-processing functions extract data from a formatted report. This example creates a trigger that uses the last value of unspecified fields. This case illustrates the following:

■

■

■

■

■

■

■

Use of SQL*Loader with an INSERT trigger. See Oracle9i Application Developer’s

Guide - Fundamentals for more information on database triggers.

Use of the SQL string to manipulate data; see Applying SQL Operators to Fields on page 6-50.

Different initial and trailing delimiters. See Specifying Delimiters on page 6-24.

Use of SYSDATE; see Setting a Column to the Current Date on page 6-56.

Use of the TRAILING NULLCOLS clause; see TRAILING NULLCOLS Clause on page 5-37.

Ambiguous field length warnings; see Conflicting Native Datatype Field

Lengths on page 6-21 and Conflicting Field Lengths for Character Datatypes on page 6-28.

Use of a discard file. See Specifying the Discard File in the Control File on page 5-14.

Creating a BEFORE INSERT Trigger

In this case study, a BEFORE INSERT trigger is required to fill in the department number, job name, and manager’s number when these fields are not present on a data line. When values are present, they should be saved in a global variable. When values are not present, the global variables are used.

The INSERT trigger and the global variables package are created when you execute the ulcase7s.sql script.

The package defining the global variables looks as follows:

CREATE OR REPLACE PACKAGE uldemo7 AS -- Global Package Variables

last_deptno NUMBER(2);

last_job VARCHAR2(9);

last_mgr NUMBER(4);

END uldemo7;

/

The definition of the INSERT trigger looks as follows:

CREATE OR REPLACE TRIGGER uldemo7_emp_insert

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Case Study 7: Extracting Data from a Formatted Report

BEFORE INSERT ON emp

FOR EACH ROW

BEGIN

IF :new.deptno IS NOT NULL THEN

uldemo7.last_deptno := :new.deptno; -- save value for later

ELSE

:new.deptno := uldemo7.last_deptno; -- use last valid value

END IF;

IF :new.job IS NOT NULL THEN

uldemo7.last_job := :new.job;

ELSE

:new.job := uldemo7.last_job;

END IF;

IF :new.mgr IS NOT NULL THEN

uldemo7.last_mgr := :new.mgr;

ELSE

:new.mgr := uldemo7.last_mgr;

END IF;

END;

/

Note:

The FOR EACH ROW clause is important. If it was not specified, the INSERT trigger would only execute once for each array of inserts, because SQL*Loader uses the array interface.

Be sure to execute the ulcase7e.sql script to drop the INSERT trigger and the global variables package before continuing with the rest of the case studies. See

Running Case Study 7 on page 10-31.

Control File for Case Study 7

The control file is ulcase7.ctl.

LOAD DATA

INFILE ’ulcase7.dat’

DISCARDFILE ’ulcase7.dis’

APPEND

INTO TABLE emp

1)

WHEN (57) = ’.’

2)

TRAILING NULLCOLS

3)

(hiredate SYSDATE,

4)

deptno POSITION(1:2) INTEGER EXTERNAL(3)

5)

NULLIF deptno=BLANKS,

SQL*Loader Case Studies

10-29

Case Study 7: Extracting Data from a Formatted Report

job POSITION(7:14) CHAR TERMINATED BY WHITESPACE

6)

NULLIF job=BLANKS "UPPER(:job)",

7)

mgr POSITION(28:31) INTEGER EXTERNAL

TERMINATED BY WHITESPACE, NULLIF mgr=BLANKS,

ename POSITION(34:41) CHAR

TERMINATED BY WHITESPACE "UPPER(:ename)",

empno POSITION(45) INTEGER EXTERNAL

TERMINATED BY WHITESPACE,

sal POSITION(51) CHAR TERMINATED BY WHITESPACE

8)

"TO_NUMBER(:sal,’$99,999.99’)",

9)

comm INTEGER EXTERNAL ENCLOSED BY ’(’ AND ’%’

":comm * 100"

)

Notes:

1.

2.

3.

4.

5.

6.

7.

The decimal point in column 57 (the salary field) identifies a line with data on it.

All other lines in the report are discarded.

The TRAILING NULLCOLS clause causes SQL*Loader to treat any fields that are missing at the end of a record as null. Because the commission field is not present for every record, this clause says to load a null commission instead of rejecting the record when only seven fields are found instead of the expected eight.

Employee’s hire date is filled in using the current system date.

This specification generates a warning message because the specified length does not agree with the length determined by the field’s position. The specified length (3) is used. See Log File for Case Study 7 on page 10-32. The length is in bytes with the default byte-length semantics. If character-length semantics were used instead, this length would be in characters.

Because the report only shows department number, job, and manager when the value changes, these fields may be blank. This control file causes them to be loaded as null, and an insert trigger fills in the last valid value.

The SQL string changes the job name to uppercase letters.

It is necessary to specify starting position here. If the job field and the manager field were both blank, then the job field’s TERMINATED BY WHITESPACE clause would cause SQL*Loader to scan forward to the employee name field. Without the POSITION clause, the employee name field would be mistakenly interpreted as the manager field.

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Case Study 7: Extracting Data from a Formatted Report

8.

9.

Here, the SQL string translates the field from a formatted character string into a number. The numeric value takes less space and can be printed with a variety of formatting options.

In this case, different initial and trailing delimiters pick the numeric value out of a formatted field. The SQL string then converts the value to its stored form.

Datafile for Case Study 7

The following listing of the report shows the data to be loaded:

Today’s Newly Hired Employees

Dept Job Manager MgrNo Emp Name EmpNo Salary/Commission

---- -------- -------- ----- -------- ----- -----------------

20 Salesman Blake 7698 Shepard 8061 $1,600.00 (3%)

Falstaff 8066 $1,250.00 (5%)

Major 8064 $1,250.00 (14%)

30 Clerk Scott 7788 Conrad 8062 $1,100.00

Ford 7369 DeSilva 8063 $800.00

Manager King 7839 Provo 8065 $2,975.00

Running Case Study 7

Take the following steps to run the case study.

1.

Start SQL*Plus as scott/tiger by entering the following at the system prompt: sqlplus scott/tiger

2.

The SQL prompt is displayed.

At the SQL prompt, execute the SQL script for this case study, as follows:

SQL> @ulcase7s

3.

This prepares and populates tables for the case study and then returns you to the system prompt.

At the system prompt, invoke SQL*Loader and run the case study, as follows: sqlldr USERID=scott/tiger CONTROL=ulcase7.ctl LOG=ulcase7.log

SQL*Loader Case Studies

10-31

Case Study 7: Extracting Data from a Formatted Report

4.

SQL*Loader extracts data from the report, creates the log file, and returns you to the system prompt. You can check the log file to see the results of running the case study.

After running this case study, you must drop the insert triggers and global-variable package before you can continue with the rest of the case studies. To do this, execute the ulcase7e.sql script as follows:

SQL> @ulcase7e

Log File for Case Study 7

The following is a portion of the log file:

1)

SQL*Loader-307: Warning: conflicting lengths 2 and 3 specified for column

DEPTNO

table EMP

Control File: ulcase7.ctl

Data File: ulcase7.dat

Bad File: ulcase7.bad

Discard File: ulcase7.dis

(Allow all discards)

Number to load: ALL

Number to skip: 0

Errors allowed: 50

Bind array: 64 rows, maximum of 256000 bytes

Continuation: none specified

Path used: Conventional

Table EMP, loaded when 57:57 = 0X2e(character ’.’)

Insert option in effect for this table: APPEND

TRAILING NULLCOLS option in effect

Column Name Position Len Term Encl Datatype

------------------------------ ---------- ----- ---- ---- ---------------------

HIREDATE SYSDATE

DEPTNO 1:2 3 CHARACTER

NULL if DEPTNO = BLANKS

JOB 7:14 8 WHT CHARACTER

NULL if JOB = BLANKS

SQL string for column : "UPPER(:job)"

MGR 28:31 4 WHT CHARACTER

NULL if MGR = BLANKS

ENAME 34:41 8 WHT CHARACTER

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Case Study 7: Extracting Data from a Formatted Report

SQL string for column : "UPPER(:ename)"

EMPNO NEXT * WHT CHARACTER

SAL 51 * WHT CHARACTER

SQL string for column : "TO_NUMBER(:sal,’$99,999.99’)"

COMM NEXT * ( CHARACTER

%

SQL string for column : ":comm * 100"

2)

Record 1: Discarded - failed all WHEN clauses.

Record 2: Discarded - failed all WHEN clauses.

Record 3: Discarded - failed all WHEN clauses.

Record 4: Discarded - failed all WHEN clauses.

Record 5: Discarded - failed all WHEN clauses.

Record 6: Discarded - failed all WHEN clauses.

Record 10: Discarded - failed all WHEN clauses.

Table EMP:

6 Rows successfully loaded.

0 Rows not loaded due to data errors.

2)

7 Rows not loaded because all WHEN clauses were failed.

0 Rows not loaded because all fields were null.

Space allocated for bind array: 51584 bytes(64 rows)

Read buffer bytes: 1048576

Total logical records skipped: 0

Total logical records read: 13

Total logical records rejected: 0

2)

Total logical records discarded: 7

Run began on Wed Feb 27 14:54:03 2002

Run ended on Wed Feb 27 14:54:04 2002

Elapsed time was: 00:00:00.99

CPU time was: 00:00:00.21

Notes:

1.

2.

A warning is generated by the difference between the specified length and the length derived from the position specification.

There are six header lines at the top of the report: 3 of them contain text and 3 of them are blank. All of them are rejected, as is the blank separator line in the middle.

SQL*Loader Case Studies

10-33

Case Study 8: Loading Partitioned Tables

Case Study 8: Loading Partitioned Tables

Case 8 demonstrates:

■

■

■

Partitioning of data. See Oracle9i Database Concepts for more information on partitioned data concepts.

Explicitly defined field positions and datatypes.

Loading using the fixed record length option. See Input Data and Datafiles on page 3-4.

Control File for Case Study 8

The control file is ulcase8.ctl. It loads the lineitem table with fixed-length records, partitioning the data according to shipment date.

LOAD DATA

1)

INFILE ’ulcase8.dat’ "fix 129"

BADFILE ’ulcase8.bad’

TRUNCATE

INTO TABLE lineitem

PARTITION (ship_q1)

2)

(l_orderkey position (1:6) char,

l_partkey position (7:11) char,

l_suppkey position (12:15) char,

l_linenumber position (16:16) char,

l_quantity position (17:18) char,

l_extendedprice position (19:26) char,

l_discount position (27:29) char,

l_tax position (30:32) char,

l_returnflag position (33:33) char,

l_linestatus position (34:34) char,

l_shipdate position (35:43) char,

l_commitdate position (44:52) char,

l_receiptdate position (53:61) char,

l_shipinstruct position (62:78) char,

l_shipmode position (79:85) char,

l_comment position (86:128) char)

Notes:

1.

Specifies that each record in the datafile is of fixed length (129 bytes in this example).

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Case Study 8: Loading Partitioned Tables

2.

Identifies the column name and location of the data in the datafile to be loaded into each column.

Table Creation

In order to partition the data, the lineitem table is created using four partitions according to the shipment date: create table lineitem

(l_orderkey number, l_partkey number, l_suppkey number, l_linenumber number, l_quantity number, l_extendedprice number, l_discount number, l_tax number, l_returnflag char, l_linestatus char, l_shipdate date, l_commitdate date, l_receiptdate date, l_shipinstruct char(17), l_shipmode char(7), l_comment char(43)) partition by range (l_shipdate)

( partition ship_q1 values less than (TO_DATE(’01-APR-1996’, ’DD-MON-YYYY’)) tablespace p01, partition ship_q2 values less than (TO_DATE(’01-JUL-1996’, ’DD-MON-YYYY’)) tablespace p02, partition ship_q3 values less than (TO_DATE(’01-OCT-1996’, ’DD-MON-YYYY’)) tablespace p03, partition ship_q4 values less than (TO_DATE(’01-JAN-1997’, ’DD-MON-YYYY’)) tablespace p04

)

Datafile for Case Study 8

The datafile for this case, ulcase8.dat, looks as follows. Each record is 128 bytes in length. Five blanks precede each record in the file.

1 151978511724386.60 7.04.0NO09-SEP-6412-FEB-9622-MAR-96DELIVER IN

PERSONTRUCK iPBw4mMm7w7kQ zNPL i261OPP

1 2731 73223658958.28.09.06NO12-FEB-9628-FEB-9620-APR-96TAKE BACK RETURN

SQL*Loader Case Studies

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Case Study 8: Loading Partitioned Tables

MAIL 5wM04SNyl0AnghCP2nx lAi

1 3370 3713 810210.96 .1.02NO29-MAR-9605-MAR-9631-JAN-96TAKE BACK RETURN

REG AIRSQC2C 5PNCy4mM

1 5214 46542831197.88.09.06NO21-APR-9630-MAR-9616-MAY-96NONE

AIR Om0L65CSAwSj5k6k

1 6564 6763246897.92.07.02NO30-MAY-9607-FEB-9603-FEB-96DELIVER IN

PERSONMAIL CB0SnyOL PQ32B70wB75k 6Aw10m0wh

1 7403 160524 31329.6 .1.04NO30-JUN-9614-MAR-9601 APR-96NONE

FOB C2gOQj OB6RLk1BS15 igN

2 8819 82012441659.44 0.08NO05-AUG-9609-FEB-9711-MAR-97COLLECT COD

AIR O52M70MRgRNnmm476mNm

3 9451 721230 41113.5.05.01AF05-SEP-9629-DEC-9318-FEB-94TAKE BACK RETURN

FOB 6wQnO0Llg6y

3 9717 1834440788.44.07.03RF09-NOV-9623-DEC-9315-FEB-94TAKE BACK RETURN

SHIP LhiA7wygz0k4g4zRhMLBAM

3 9844 1955 6 8066.64.04.01RF28-DEC-9615-DEC-9314-FEB-94TAKE BACK RETURN

REG AIR6nmBmjQkgiCyzCQBkxPPOx5j4hB 0lRywgniP1297

Running Case Study 8

Take the following steps to run the case study.

1.

Start SQL*Plus as scott/tiger by entering the following at the system prompt: sqlplus scott/tiger

2.

The SQL prompt is displayed.

At the SQL prompt, execute the SQL script for this case study, as follows:

SQL> @ulcase8

3.

This prepares and populates tables for the case study and then returns you to the system prompt.

At the system prompt, invoke SQL*Loader and run the case study, as follows: sqlldr USERID=scott/tiger CONTROL=ulcase8.ctl LOG=ulcase8.log

SQL*Loader partitions and loads the data, creates the log file, and returns you to the system prompt. You can check the log file to see the results of running the case study.

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Case Study 8: Loading Partitioned Tables

Log File for Case Study 8

The following shows a portion of the log file:

Control File: ulcase8.ctl

Data File: ulcase8.dat

File processing option string: "fix 129"

Bad File: ulcase8.bad

Discard File: none specified

(Allow all discards)

Number to load: ALL

Number to skip: 0

Errors allowed: 50

Bind array: 64 rows, maximum of 256000 bytes

Continuation: none specified

Path used: Conventional

Table LINEITEM, partition SHIP_Q1, loaded from every logical record.

Insert option in effect for this partition: TRUNCATE

Column Name Position Len Term Encl Datatype

------------------------------ ---------- ----- ---- ---- ---------------------

L_ORDERKEY 1:6 6 CHARACTER

L_PARTKEY 7:11 5 CHARACTER

L_SUPPKEY 12:15 4 CHARACTER

L_LINENUMBER 16:16 1 CHARACTER

L_QUANTITY 17:18 2 CHARACTER

L_EXTENDEDPRICE 19:26 8 CHARACTER

L_DISCOUNT 27:29 3 CHARACTER

L_TAX 30:32 3 CHARACTER

L_RETURNFLAG 33:33 1 CHARACTER

L_LINESTATUS 34:34 1 CHARACTER

L_SHIPDATE 35:43 9 CHARACTER

L_COMMITDATE 44:52 9 CHARACTER

L_RECEIPTDATE 53:61 9 CHARACTER

L_SHIPINSTRUCT 62:78 17 CHARACTER

L_SHIPMODE 79:85 7 CHARACTER

L_COMMENT 86:128 43 CHARACTER

Record 4: Rejected - Error on table LINEITEM, partition SHIP_Q1.

ORA-14401: inserted partition key is outside specified partition

Record 5: Rejected - Error on table LINEITEM, partition SHIP_Q1.

SQL*Loader Case Studies

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Case Study 9: Loading LOBFILEs (CLOBs)

ORA-14401: inserted partition key is outside specified partition

Record 6: Rejected - Error on table LINEITEM, partition SHIP_Q1.

ORA-14401: inserted partition key is outside specified partition

Record 7: Rejected - Error on table LINEITEM, partition SHIP_Q1.

ORA-14401: inserted partition key is outside specified partition

Record 8: Rejected - Error on table LINEITEM, partition SHIP_Q1.

ORA-14401: inserted partition key is outside specified partition

Record 9: Rejected - Error on table LINEITEM, partition SHIP_Q1.

ORA-14401: inserted partition key is outside specified partition

Record 10: Rejected - Error on table LINEITEM, partition SHIP_Q1.

ORA-14401: inserted partition key is outside specified partition

Table LINEITEM, partition SHIP_Q1:

3 Rows successfully loaded.

7 Rows not loaded due to data errors.

0 Rows not loaded because all WHEN clauses were failed.

0 Rows not loaded because all fields were null.

Space allocated for bind array: 11008 bytes(64 rows)

Read buffer bytes: 1048576

Total logical records skipped: 0

Total logical records read: 10

Total logical records rejected: 7

Total logical records discarded: 0

Run began on Wed Feb 27 15:02:28 2002

Run ended on Wed Feb 27 15:02:29 2002

Elapsed time was: 00:00:01.37

CPU time was: 00:00:00.20

Case Study 9: Loading LOBFILEs (CLOBs)

Case 9 demonstrates:

■

Adding a CLOB column called resume to the table emp

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Oracle9 i

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Case Study 9: Loading LOBFILEs (CLOBs)

■

■

Using a filler field (res_file)

Loading multiple LOBFILEs into the emp table

Control File for Case Study 9

The control file is ulcase9.ctl. It loads new records into emp, including a resume for each employee. Each resume is contained in a separate file.

LOAD DATA

INFILE *

INTO TABLE emp

REPLACE

FIELDS TERMINATED BY ’,’

( empno INTEGER EXTERNAL,

ename CHAR,

job CHAR,

mgr INTEGER EXTERNAL,

sal DECIMAL EXTERNAL,

comm DECIMAL EXTERNAL,

deptno INTEGER EXTERNAL,

1)

res_file FILLER CHAR,

2)

"RESUME" LOBFILE (res_file) TERMINATED BY EOF NULLIF res_file = ’NONE’

)

BEGINDATA

7782,CLARK,MANAGER,7839,2572.50,,10,ulcase91.dat

7839,KING,PRESIDENT,,5500.00,,10,ulcase92.dat

7934,MILLER,CLERK,7782,920.00,,10,ulcase93.dat

7566,JONES,MANAGER,7839,3123.75,,20,ulcase94.dat

7499,ALLEN,SALESMAN,7698,1600.00,300.00,30,ulcase95.dat

7654,MARTIN,SALESMAN,7698,1312.50,1400.00,30,ulcase96.dat

7658,CHAN,ANALYST,7566,3450.00,,20,NONE

Notes:

1.

This is a filler field. The filler field is assigned values from the data field to which it is mapped. See Specifying Filler Fields on page 6-6 for more information.

2.

The resume column is loaded as a CLOB. The LOBFILE function specifies the field name in which the name of the file that contains data for the LOB field is provided. See Loading LOB Data from LOBFILEs on page 7-23 for more information.

SQL*Loader Case Studies

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Case Study 9: Loading LOBFILEs (CLOBs)

Datafiles for Case Study 9

>>ulcase91.dat<<

Resume for Mary Clark

Career Objective: Manage a sales team with consistent record-breaking

performance.

Education: BA Business University of Iowa 1992

Experience: 1992-1994 - Sales Support at MicroSales Inc.

Won "Best Sales Support" award in 1993 and 1994

1994-Present - Sales Manager at MicroSales Inc.

Most sales in mid-South division for 2 years

>>ulcase92.dat<<

Resume for Monica King

Career Objective: President of large computer services company

Education: BA English Literature Bennington, 1985

Experience: 1985-1986 - Mailroom at New World Services

1986-1987 - Secretary for sales management at

New World Services

1988-1989 - Sales support at New World Services

1990-1992 - Salesman at New World Services

1993-1994 - Sales Manager at New World Services

1995 - Vice President of Sales and Marketing at

New World Services

1996-Present - President of New World Services

>>ulcase93.dat<<

Resume for Dan Miller

Career Objective: Work as a sales support specialist for a services

company

Education: Plainview High School, 1996

Experience: 1996 - Present: Mail room clerk at New World Services

>>ulcase94.dat<<

Resume for Alyson Jones

Career Objective: Work in senior sales management for a vibrant and

growing company

Education: BA Philosophy Howard Univerity 1993

Experience: 1993 - Sales Support for New World Services

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Oracle9 i

Database Utilities

Case Study 9: Loading LOBFILEs (CLOBs)

1994-1995 - Salesman for New World Services. Led in

US sales in both 1994 and 1995.

1996 - present - Sales Manager New World Services. My

sales team has beat its quota by at least 15% each

year.

>>ulcase95.dat<<

Resume for David Allen

Career Objective: Senior Sales man for agressive Services company

Education: BS Business Administration, Weber State 1994

Experience: 1993-1994 - Sales Support New World Services

1994-present - Salesman at New World Service. Won sales

award for exceeding sales quota by over 20%

in 1995, 1996.

>>ulcase96.dat<<

Resume for Tom Martin

Career Objective: Salesman for a computing service company

Education: 1988 - BA Mathematics, University of the North

Experience: 1988-1992 Sales Support, New World Services

1993-present Salesman New World Services

Running Case Study 9

Take the following steps to run the case study.

1.

Start SQL*Plus as scott/tiger by entering the following at the system prompt: sqlplus scott/tiger

2.

The SQL prompt is displayed.

At the SQL prompt, execute the SQL script for this case study, as follows:

SQL> @ulcase9

3.

This prepares and populates tables for the case study and then returns you to the system prompt.

At the system prompt, invoke SQL*Loader and run the case study, as follows: sqlldr USERID=scott/tiger CONTROL=ulcase9.ctl LOG=ulcase9.log

SQL*Loader Case Studies

10-41

Case Study 9: Loading LOBFILEs (CLOBs)

SQL*Loader loads the emp table, creates the log file, and returns you to the system prompt. You can check the log file to see the results of running the case study.

Log File for Case Study 9

The following shows a portion of the log file:

Control File: ulcase9.ctl

Data File: ulcase9.ctl

Bad File: ulcase9.bad

Discard File: none specified

(Allow all discards)

Number to load: ALL

Number to skip: 0

Errors allowed: 50

Bind array: 64 rows, maximum of 256000 bytes

Continuation: none specified

Path used: Conventional

Table EMP, loaded from every logical record.

Insert option in effect for this table: REPLACE

Column Name Position Len Term Encl Datatype

------------------------------ ---------- ----- ---- ---- ---------------------

EMPNO FIRST * , CHARACTER

ENAME NEXT * , CHARACTER

JOB NEXT * , CHARACTER

MGR NEXT * , CHARACTER

SAL NEXT * , CHARACTER

COMM NEXT * , CHARACTER

DEPTNO NEXT * , CHARACTER

RES_FILE NEXT * , CHARACTER

(FILLER FIELD)

"RESUME" DERIVED * EOF CHARACTER

Dynamic LOBFILE. Filename in field RES_FILE

NULL if RES_FILE = 0X4e4f4e45(character ’NONE’)

Table EMP:

7 Rows successfully loaded.

0 Rows not loaded due to data errors.

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Case Study 10: Loading REF Fields and VARRAYs

0 Rows not loaded because all WHEN clauses were failed.

0 Rows not loaded because all fields were null.

Space allocated for bind array: 132096 bytes(64 rows)

Read buffer bytes: 1048576

Total logical records skipped: 0

Total logical records read: 7

Total logical records rejected: 0

Total logical records discarded: 0

Run began on Wed Feb 27 15:06:49 2002

Run ended on Wed Feb 27 15:06:50 2002

Elapsed time was: 00:00:01.01

CPU time was: 00:00:00.20

Case Study 10: Loading REF Fields and VARRAYs

Case 10 demonstrates:

■

Loading a customer table that has a primary key as its OID and stores order items in a VARRAY.

■

Loading an order table that has a reference to the customer table and the order items in a VARRAY.

Note:

Case study 10 requires that the COMPATIBILITY parameter be set to 8.1.0 or higher in your initialization parameter file.

Otherwise, the table cannot be properly created and you will receive an error message. For more information on setting the

COMPATIBILITY

parameter, see Oracle9i Database Migration.

Control File for Case Study 10

LOAD DATA

INFILE *

CONTINUEIF THIS (1) = ’*’

INTO TABLE customers

REPLACE

FIELDS TERMINATED BY ","

(

SQL*Loader Case Studies

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Case Study 10: Loading REF Fields and VARRAYs

CUST_NO CHAR,

NAME CHAR,

ADDR CHAR

)

INTO TABLE orders

REPLACE

FIELDS TERMINATED BY ","

(

order_no CHAR,

1)

cust_no FILLER CHAR,

2)

cust REF (CONSTANT ’CUSTOMERS’, cust_no),

1)

item_list_count FILLER CHAR,

3)

item_list VARRAY COUNT (item_list_count)

(

4)

item_list COLUMN OBJECT

(

5)

item CHAR,

cnt CHAR,

price CHAR

)

)

)

6)

BEGINDATA

*00001,Spacely Sprockets,15 Space Way,

*00101,00001,2,

*Sprocket clips, 10000, .01,

*Sprocket cleaner, 10, 14.00

*00002,Cogswell Cogs,12 Cogswell Lane,

*00100,00002,4,

*one quarter inch cogs,1000,.02,

*one half inch cog, 150, .04,

*one inch cog, 75, .10,

*Custom coffee mugs, 10, 2.50

Notes:

1.

This is a FILLER field. The FILLER field is assigned values from the data field to which it is mapped. See Specifying Filler Fields on page 6-6 for more information.

2.

3.

This field is created as a REF field. See Loading REF Columns on page 7-15 for more information.

item_list

is stored in a VARRAY.

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Oracle9 i

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Case Study 10: Loading REF Fields and VARRAYs

4.

5.

6.

The second occurrence of item_list identifies the datatype of each element of the VARRAY. Here, the datatype is a COLUMN OBJECT.

This list shows all attributes of the column object that are loaded for the

VARRAY

. The list is enclosed in parentheses. See Loading Column Objects on page 7-1 for more information.

The data is contained in the control file and is preceded by the BEGINDATA parameter.

Running Case Study 10

Take the following steps to run the case study.

1.

Start SQL*Plus as scott/tiger by entering the following at the system prompt: sqlplus scott/tiger

2.

The SQL prompt is displayed.

At the SQL prompt, execute the SQL script for this case study, as follows:

SQL> @ulcase10

3.

This prepares and populates tables for the case study and then returns you to the system prompt.

At the system prompt, invoke SQL*Loader and run the case study, as follows: sqlldr USERID=scott/tiger CONTROL=ulcase10.ctl LOG=ulcase10.log

SQL*Loader loads the data, creates the log file, and returns you to the system prompt. You can check the log file to see the results of running the case study.

Log File for Case Study 10

The following shows a portion of the log file:

Control File: ulcase10.ctl

Data File: ulcase10.ctl

Bad File: ulcase10.bad

Discard File: none specified

(Allow all discards)

Number to load: ALL

SQL*Loader Case Studies

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Case Study 10: Loading REF Fields and VARRAYs

Number to skip: 0

Errors allowed: 50

Bind array: 64 rows, maximum of 256000 bytes

Continuation: 1:1 = 0X2a(character ’*’), in current physical record

Path used: Conventional

Table CUSTOMERS, loaded from every logical record.

Insert option in effect for this table: REPLACE

Column Name Position Len Term Encl Datatype

------------------------------ ---------- ----- ---- ---- ---------------------

CUST_NO FIRST * , CHARACTER

NAME NEXT * , CHARACTER

ADDR NEXT * , CHARACTER

Table ORDERS, loaded from every logical record.

Insert option in effect for this table: REPLACE

Column Name Position Len Term Encl Datatype

------------------------------ ---------- ----- ---- ---- ---------------------

ORDER_NO NEXT * , CHARACTER

CUST_NO NEXT * , CHARACTER

(FILLER FIELD)

CUST DERIVED REF

Arguments are:

CONSTANT ’CUSTOMERS’

CUST_NO

ITEM_LIST_COUNT NEXT * , CHARACTER

(FILLER FIELD)

ITEM_LIST DERIVED * VARRAY

Count for VARRAY

ITEM_LIST_COUNT

*** Fields in ITEM_LIST

ITEM_LIST DERIVED * COLUMN OBJECT

*** Fields in ITEM_LIST.ITEM_LIST

ITEM FIRST * , CHARACTER

CNT NEXT * , CHARACTER

PRICE NEXT * , CHARACTER

*** End of fields in ITEM_LIST.ITEM_LIST

*** End of fields in ITEM_LIST

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Case Study 11: Loading Data in the Unicode Character Set

Table CUSTOMERS:

2 Rows successfully loaded.

0 Rows not loaded due to data errors.

0 Rows not loaded because all WHEN clauses were failed.

0 Rows not loaded because all fields were null.

Table ORDERS:

2 Rows successfully loaded.

0 Rows not loaded due to data errors.

0 Rows not loaded because all WHEN clauses were failed.

0 Rows not loaded because all fields were null.

Space allocated for bind array: 149120 bytes(64 rows)

Read buffer bytes: 1048576

Total logical records skipped: 0

Total logical records read: 2

Total logical records rejected: 0

Total logical records discarded: 0

Run began on Wed Feb 27 14:05:29 2002

Run ended on Wed Feb 27 14:05:31 2002

Elapsed time was: 00:00:02.07

CPU time was: 00:00:00.20

Case Study 11: Loading Data in the Unicode Character Set

In this case study, SQL*Loader loads data from a datafile in a Unicode character set.

This case study parallels case study 3, except that it uses the character set UTF16 and a maximum length is specified for the empno and deptno fields. The data must be in a separate datafile because the CHARACTERSET keyword is specified. This case study demonstrates the following:

■

Using SQL*Loader to load data in the Unicode character set, UTF16.

■

■

■

Using SQL*Loader to load data in a fixed-width multibyte character set.

Using character-length semantics.

Using SQL*Loader to load data in little endian byte order. SQL*Loader checks the byte order of the system on which it is running. If necessary, SQL*Loader

SQL*Loader Case Studies

10-47

Case Study 11: Loading Data in the Unicode Character Set swaps the byte order of the data to ensure that any byte-order-dependent data is correctly loaded.

Control File for Case Study 11

The control file is ulcase11.ctl.

LOAD DATA

1)

CHARACTERSET UTF16

2)

BYTEORDER LITTLE

INFILE ulcase11.dat

REPLACE

INTO TABLE emp

3)

FIELDS TERMINATED BY X’002c’ OPTIONALLY ENCLOSED BY X’0022’

4)

(empno INTEGER EXTERNAL (5), ename, job, mgr,

hiredate DATE(20) "DD-Month-YYYY",

sal, comm,

5)

deptno CHAR(5) TERMINATED BY ":",

projno,

loadseq SEQUENCE(MAX,1) )

Notes:

1.

2.

3.

The character set specified with the CHARACTERSET keyword is UTF16.

SQL*Loader will convert the data from the UTF16 character set to the datafile character set. This line also tells SQL*Loader to use character-length semantics for the load.

BYTEORDER LITTLE

tells SQL*Loader that the data in the datafile is in little endian byte order. SQL*Loader checks the byte order of the system on which it is running to determine if any byte-swapping is necessary. In this example, all the character data in UTF16 is byte-order dependent.

The TERMINATED BY and OPTIONALLY ENCLOSED BY clauses both specify hexadecimal strings. The X’002c’ is the encoding for a comma (,) in UTF-16 big endian format. The X’0022’ is the encoding for a double quotation mark

(") in big endian format. Because the datafile is in little endian format,

SQL*Loader swaps the bytes before checking for a match.

If these clauses were specified as character strings instead of hexadecimal strings, SQL*Loader would convert the strings to the datafile character set

(UTF16) and byte-swap as needed before checking for a match.

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Case Study 11: Loading Data in the Unicode Character Set

4.

5.

Because character-length semantics are used, the maximum length for the empno

, hiredate, and deptno fields is interpreted as characters, not bytes.

The TERMINATED BY clause for the deptno field is specified using the character string ":". SQL*Loader converts the string to the datafile character set

(UTF16) and byte-swaps as needed before checking for a match.

See Also:

■

■

Handling Different Character Encoding Schemes on page 5-16

Byte Ordering on page 6-37

Datafile for Case Study 11

7782, "Clark", "Manager", 7839, 09-June-1981, 2572.50,, 10:101

7839, "King", "President", , 17-November-1981, 5500.00,, 10:102

7934, "Miller", "Clerk", 7782, 23-January-1982, 920.00,, 10:102

7566, "Jones", "Manager", 7839, 02-April-1981, 3123.75,, 20:101

7499, "Allen", "Salesman", 7698, 20-February-1981, 1600.00, 300.00, 30:103

7654, "Martin", "Salesman", 7698, 28-September-1981, 1312.50, 1400.00, 30:103

7658, "Chan", "Analyst", 7566, 03-May-1982, 3450,, 20:101

Running Case Study 11

Take the following steps to run the case study.

1.

Start SQL*Plus as scott/tiger by entering the following at the system prompt: sqlplus scott/tiger

2.

The SQL prompt is displayed.

At the SQL prompt, execute the SQL script for this case study, as follows:

SQL> @ulcase11

3.

This prepares the table emp for the case study and then returns you to the system prompt.

At the system prompt, invoke SQL*Loader and run the case study, as follows: sqlldr USERID=scott/tiger CONTROL=ulcase11.ctl LOG=ulcase11.log

SQL*Loader Case Studies

10-49

Case Study 11: Loading Data in the Unicode Character Set

SQL*Loader loads the table emp, creates the log file, and returns you to the system prompt. You can check the log file to see the results of running the case study.

Log File for Case Study 11

The following shows a portion of the log file for case study 11:

Control File: ulcase11.ctl

Character Set utf16 specified for all input.

1)

Using character length semantics.

2)

Byteorder little endian specified.

Processing datafile as little endian.

3)

SQL*Loader running on a big endian platform. Swapping bytes where needed.

Data File: ulcase11.dat

Bad File: ulcase11.bad

Discard File: none specified

(Allow all discards)

Number to load: ALL

Number to skip: 0

Errors allowed: 50

Bind array: 64 rows, maximum of 256000 bytes

Continuation: none specified

Path used: Conventional

Table EMP, loaded from every logical record.

Insert option in effect for this table: REPLACE

Column Name Position Len Term Encl Datatype

------------------------------ ---------- ----- ---- ---- ---------------------

4)

EMPNO FIRST 10 , O(") CHARACTER

ENAME NEXT * , O(") CHARACTER

JOB NEXT * , O(") CHARACTER

MGR NEXT * , O(") CHARACTER

4)

HIREDATE NEXT 40 , O(") DATE DD-Month-YYYY

SAL NEXT * , O(") CHARACTER

COMM NEXT * , O(") CHARACTER

DEPTNO NEXT 10 : O(") CHARACTER

4)

PROJNO NEXT * , O(") CHARACTER

LOADSEQ SEQUENCE (MAX, 1)

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Case Study 11: Loading Data in the Unicode Character Set

Table EMP:

7 Rows successfully loaded.

0 Rows not loaded due to data errors.

0 Rows not loaded because all WHEN clauses were failed.

0 Rows not loaded because all fields were null.

Space allocated for bind array: 104768 bytes(64 rows)

Read buffer bytes: 1048576

Total logical records skipped: 0

Total logical records read: 7

Total logical records rejected: 0

Total logical records discarded: 0

Run began on Wed Feb 27 16:33:47 2002

Run ended on Wed Feb 27 16:33:49 2002

Elapsed time was: 00:00:01.74

CPU time was: 00:00:00.20

Notes:

1.

2.

3.

4.

SQL*Loader used character-length semantics for this load. This is the default if the character set is UTF16. This means that length checking for the maximum sizes is in characters (see item number 4 in this list).

BYTEORDER LITTLE was specified in the control file. This tells SQL*Loader that the byte order for the UTF16 character data in the datafile is little endian.

This message only appears when SQL*Loader is running on a system with the opposite byte order (in this case, big endian) from the datafile’s byte order. It indicates that SQL*Loader detected that the byte order of the datafile is opposite from the byte order of the system on which SQL*Loader is running.

Therefore, SQL*Loader had to byte-swap any byte-order-dependent data (in this case, all the UTF16 character data).

The maximum lengths under the len heading are in bytes even though character-length semantics were used. However, the maximum lengths are adjusted based on the maximum size, in bytes, of a character in UTF16. All characters in UTF16 are 2 bytes. Therefore, the sizes given for empno and projno

(5) are multiplied by 2, resulting in a maximum size of 10 bytes.

Similarly, the hiredate maximum size (20) is multiplied by 2, resulting in a maximum size of 40 bytes.

SQL*Loader Case Studies

10-51

Case Study 11: Loading Data in the Unicode Character Set

Loaded Tables for Case Study 11

To see the results of this execution of SQL*Loader, execute the following query at the SQL prompt:

SQL> SELECT * FROM emp;

The results of the query look as follows (the formatting may be slightly different on your display):

EMPNO ENAME JOB MGR HIREDATE SAL COMM DEPTNO PROJNO LOADSEQ

------ ------ --------- ----- --------- -------- ----- ------- ------ --------

7782 Clark Manager 7839 09-JUN-81 2572.50 10 101 1

7839 King President 17-NOV-81 5500.00 10 102 2

7934 Miller Clerk 7782 23-JAN-82 920.00 10 102 3

7566 Jones Manager 7839 02-APR-81 3123.75 20 101 4

EMPNO ENAME JOB MGR HIREDATE SAL COMM DEPTNO PROJNO LOADSEQ

------ ------ --------- ----- --------- -------- ----- ------- ------ --------

7499 Allen Salesman 7698 20-FEB-81 1600.00 300 30 103 5

7654 Martin Salesman 7698 28-SEP-81 1312.50 1400 30 103 6

7658 Chan Analyst 7566 03-MAY-82 3450.00 20 101 7

7 rows selected.

The output for the table is displayed in the character set US7ASCII, which is the normal default character set when the NLS_LANG parameter is not defined.

SQL*Loader converts the output from the database character set, which normally defaults to WE8DEC, to the character set specified for your session by the NLS_

LANG

parameter.

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Part III

External Tables

The chapters in this section describe the use of external tables.

Chapter 11, "External Tables Concepts"

This chapter describes basic concepts about external tables.

Chapter 12, "External Tables Access Parameters"

This chapter describes the access parameters used to interface with the external tables API.