9 SQL*Loader Control File Reference
The SQL*Loader control file is a text file that contains data definition language (DDL) instructions for a SQL*Loader job.
Successfully using a SQL*Loader control file requires an understanding of the following topics:
Note:
You can also use SQL*Loader without a control file; this is known as SQL*Loader express mode. See SQL*Loader Express for more information.
- Control File Contents
The SQL*Loader control file is a text file that contains data definition language (DDL) instructions. - Specifying Command-Line Parameters in the Control File
You can specify command-line parameters in the SQL*Loader control file using theOPTIONS
clause. - Specifying File Names and Object Names
In general, SQL*Loader follows the SQL standard for specifying object names (for example, table and column names). - Identifying XMLType Tables
TheXMLTYPE
clause is available for use in a SQL*Loader control file. - Specifying Field Order
You can use theFIELD
NAMES
clause in the SQL*Loader control file to specify field order. - Specifying Data Files
To specify a data file that contains the data to be loaded, use theINFILE
keyword, followed by the file name and optional file processing options string. - Specifying CSV Format Files
To direct SQL*Loader to access the data files as comma-separated-values format files, use theCSV
clause. - Identifying Data in the Control File with BEGINDATA
Specify theBEGINDATA
statement before the first data record. - Specifying Data File 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. - 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 caused Oracle errors. - Specifying the Discard File
During execution, SQL*Loader can create a discard file for records that do not meet any of the loading criteria. - Specifying a NULLIF Clause At the Table Level
You can specify aNULLIF
clause at the table level. - Specifying Datetime Formats At the Table Level
You can specify certain datetime formats at the table level in a SQL*Loader control file. - Handling Different Character Encoding Schemes
SQL*Loader supports different character encoding schemes (called character sets, or code pages). - Interrupted Loads
Loads are interrupted and discontinued for several reasons. - Assembling Logical Records from Physical Records
This section describes assembling logical records from physical records. - Loading Logical Records into Tables
This section describes loading logical records into tables. - Index Options
This section describes index options. - Benefits of Using Multiple INTO TABLE Clauses
These sections describe the benefits of using multiple INTO TABLE clauses. - Bind Arrays and Conventional Path Loads
Multiple rows are read at one time and stored in the bind array.
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 SQL*Loader Syntax Diagrams for syntax diagrams of the SQL*Loader DDL.
To create the SQL*Loader control file, use a text editor such as vi or xemacs.
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 9-1 shows a sample control file.
Example 9-1 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)", 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:
-
This is how comments are entered in a control file. See Comments in the Control File.
-
The
LOAD DATA
statement tells SQL*Loader that this is the beginning of a new data load. See SQL*Loader Syntax Diagrams for syntax information. -
The
INFILE
clause specifies the name of a data file containing the data you want to load. See Specifying Data Files. -
The
BADFILE
clause specifies the name of a file into which rejected records are placed. See Specifying the Bad File. -
The
DISCARDFILE
clause specifies the name of a file into which discarded records are placed. See Specifying the Discard File. -
The
APPEND
clause is one of the options you can use when loading data into a table that is not empty. See Loading Data into Nonempty Tables.To load data into a table that is empty, you would use the
INSERT
clause. See Loading Data into Empty Tables. -
The
INTO TABLE
clause enables you to identify tables, fields, and data types. It defines the relationship between records in the data file and tables in the database. See Specifying Table Names. -
The
WHEN
clause specifies one or more field conditions. SQL*Loader decides whether to load the data based on these field conditions. See Loading Records Based on a Condition. -
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. -
The remainder of the control file contains the field list, which provides information about column formats in the table being loaded. See SQL*Loader Field List Reference for information about that section of the control file.
- Comments in the Control File
Comments can appear anywhere in the parameter section of the file, but they should not appear within the data.
Specifying Command-Line Parameters in the Control File
You can specify command-line parameters in the SQL*Loader control file using the OPTIONS
clause.
This can be useful if you often use a control file with the same set of options. The OPTIONS
clause precedes the LOAD
DATA
statement.
- OPTIONS Clause
The following command-line parameters can be specified using theOPTIONS
clause. - Specifying the Number of Default Expressions to Be Evaluated At One Time
Use the SQL*LoaderDEFAULT EXPRESSION CACHE n
clause to specify how many default expressions are evaluated at a time by the direct path load. The default value is 100.
OPTIONS Clause
The following command-line parameters can be specified using the OPTIONS
clause.
These parameters are described in greater detail in SQL*Loader Command-Line Reference.
BINDSIZE = n
COLUMNARRAYROWS = n
DATE_CACHE = n
DEGREE_OF_PARALLELISM= {degree-num|DEFAULT|AUTO|NONE}
DIRECT = {TRUE | FALSE}
EMPTY_LOBS_ARE_NULL = {TRUE | FALSE}
ERRORS = n
EXTERNAL_TABLE = {NOT_USED | GENERATE_ONLY | EXECUTE}
FILE = tablespace file
LOAD = n
MULTITHREADING = {TRUE | FALSE}
PARALLEL = {TRUE | FALSE}
READSIZE = n
RESUMABLE = {TRUE | FALSE}
RESUMABLE_NAME = 'text string'
RESUMABLE_TIMEOUT = n
ROWS = n
SDF_PREFIX = string
SILENT = {HEADER | FEEDBACK | ERRORS | DISCARDS | PARTITIONS | ALL}
SKIP = n
SKIP_INDEX_MAINTENANCE = {TRUE | FALSE}
SKIP_UNUSABLE_INDEXES = {TRUE | FALSE}
STREAMSIZE = n
TRIM= {LRTRIM|NOTRIM|LTRIM|RTRIM|LDRTRIM}
The following is an example use of the OPTIONS
clause that you could use in a SQL*Loader control file:
OPTIONS (BINDSIZE=100000, SILENT=(ERRORS, FEEDBACK) )
Note:
Parameter values specified on the command line override parameter values specified in the control file OPTIONS
clause.
Specifying the Number of Default Expressions to Be Evaluated At One Time
Use the SQL*Loader DEFAULT EXPRESSION CACHE n
clause to specify how many default expressions are evaluated at a time by the direct path load. The default value is 100.
Using the DEFAULT EXPRESSION CACHE
clause can significantly improve performance when default column expressions that include sequences are evaluated.
At the end of the load there may be sequence numbers left in the cache that never get used. This can happen when the number of rows to load is not a multiple of n
. If you require no loss of sequence numbers, then specify a value of 1 for this clause.
Specifying File Names and Object Names
In general, SQL*Loader follows the SQL standard for specifying object names (for example, table and column names).
- File Names That Conflict with SQL and SQL*Loader Reserved Words
SQL and SQL*Loader reserved words must be specified within double quotation marks. - Specifying SQL Strings
The SQL string applies SQL operators to data fields. - Operating System Considerations
Your course of action may depend on the operating system that you are using.
File Names 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:
Specifying SQL Strings
The SQL string applies SQL operators to data fields.
You must specify SQL strings within double quotation marks.
See Also:
Operating System Considerations
Your course of action may depend on the operating system that you are using.
The following sections discuss situations in which your course of action may depend on the operating system that you are using.
- Specifying a Complete Path
Specifying the path name within single quotation marks prevents errors. - 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 backslash escape character (\), if the escape character is allowed on your operating system. - 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. - Using the Backslash as an Escape Character
Use the backslash character to separate directories in a path name. - Escape Character Is Sometimes Disallowed
The release of the Oracle database running on your operating system may not implement the escape character for nonportable strings.
Specifying a Complete Path
Specifying the path name within single quotation marks prevents errors.
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.
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 backslash 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.
Using the Backslash as an Escape Character
Use the backslash character to separate directories in a path name.
If your operating system uses the backslash character to separate directories in a path name, and if the release of the Oracle database running on your operating system implements the backslash escape character for file names and other nonportable strings, then you must specify double backslashes in your path names and use single quotation marks.
Escape Character Is Sometimes Disallowed
The release of the Oracle database 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.
Identifying XMLType Tables
The XMLTYPE
clause is available for use in a SQL*Loader control file.
As of Oracle Database 10g, the XMLTYPE
clause is available for use in a SQL*Loader control file. This clause is of the format XMLTYPE(field name)
. It is used to identify XMLType
tables so that the correct SQL statement can be constructed. Example 9-2 shows how the XMLTYPE
clause can be used in a SQL*Loader control file to load data into a schema-based XMLType
table.
See Also:
Oracle XML DB Developer's Guide for more information about loading XML data using SQL*Loader
Example 9-2 Identifying XMLType Tables in the SQL*Loader Control File
The XML schema definition is as follows. It registers the XML schema, xdb_user.xsd
, in the Oracle XML DB, and then creates the table, xdb_tab5
.
begin dbms_xmlschema.registerSchema('xdb_user.xsd', '<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema" xmlns:xdb="http://xmlns.oracle.com/xdb"> <xs:element name = "Employee" xdb:defaultTable="EMP31B_TAB"> <xs:complexType> <xs:sequence> <xs:element name = "EmployeeId" type = "xs:positiveInteger"/> <xs:element name = "Name" type = "xs:string"/> <xs:element name = "Salary" type = "xs:positiveInteger"/> <xs:element name = "DeptId" type = "xs:positiveInteger" xdb:SQLName="DEPTID"/> </xs:sequence> </xs:complexType> </xs:element> </xs:schema>', TRUE, TRUE, FALSE); end; /
The table is defined as follows:
CREATE TABLE xdb_tab5 OF XMLTYPE XMLSCHEMA "xdb_user.xsd" ELEMENT "Employee";
The control file used to load data into the table, xdb_tab5
, looks as follows. It loads XMLType
data using the registered XML schema, xdb_user.xsd
. The XMLTYPE
clause is used to identify this table as an XMLType
table. Either direct path or conventional mode can be used to load the data into the table.
LOAD DATA INFILE * INTO TABLE xdb_tab5 TRUNCATE xmltype(xmldata) ( xmldata char(4000) ) BEGINDATA <Employee> <EmployeeId>111</EmployeeId> <Name>Ravi</Name> <Salary>100000</Sal ary> <DeptId>12</DeptId></Employee> <Employee> <EmployeeId>112</EmployeeId> <Name>John</Name> <Salary>150000</Sal ary> <DeptId>12</DeptId></Employee> <Employee> <EmployeeId>113</EmployeeId> <Name>Michael</Name> <Salary>75000</S alary> <DeptId>12</DeptId></Employee> <Employee> <EmployeeId>114</EmployeeId> <Name>Mark</Name> <Salary>125000</Sal ary> <DeptId>16</DeptId></Employee> <Employee> <EmployeeId>115</EmployeeId> <Name>Aaron</Name> <Salary>600000</Sa lary> <DeptId>16</DeptId></Employee>
Specifying Field Order
You can use the FIELD
NAMES
clause in the SQL*Loader control file to specify field order.
The syntax is as follows:
FIELD NAMES {FIRST FILE|FIRST FILE IGNORE|ALL FILES|ALL FILES IGNORE|NONE}
The FIELD
NAMES
options are:
-
FIRST
FILE
: Indicates that the first data file contains a list of field names for the data in the first record. This list uses the same delimiter as the data in the data file. The record is read for setting up the mapping between the fields in the data file and the columns in the target table. The record is skipped when the data is processed. This can be useful if the order of the fields in the data file is different from the order of the columns in the table, or if the number of fields in the data file is different from the number of columns in the target table -
FIRST
FILE
IGNORE
: Indicates that the first data file contains a list of field names for the data in the first record, but that the information should be ignored. The record will be skipped when the data is processed, but it will not be used for setting up the fields. -
ALL
FILES
: Indicates that all data files contain a list of field names for the data in the first record. The first record is skipped in each data file when the data is processed. The fields can be in a different order in each data file. SQL*Loader sets up the load based on the order of the fields in each data file. -
ALL
FILES
IGNORE
: Indicates that all data files contain a list of field names for the data in the first record, but that the information should be ignored. The record is skipped when the data is processed in every data file, but it will not be used for setting up the fields. -
NONE
: Indicates that the data file contains normal data in the first record. This is the default.
The FIELD
NAMES
clause cannot be used for complex column types such as column objects, nested tables, or VARRAYs.
Specifying Data Files
To specify a data file that contains the data to be loaded, use the INFILE
keyword, followed by the file name and optional file processing options string.
You can specify multiple single files by using multiple INFILE
keywords. You can also use wildcards in the file names (an asterisk (*) for multiple characters and a question mark (?) for a single character).
Note:
You can also specify the data file from the command line, using the DATA
parameter described in Command-Line Parameters for SQL*Loader. A file name specified on the command line overrides the first INFILE
clause in the control file.
If no file name is specified, then the file name defaults to the control file name with an extension or file type of .dat
.
If the control file itself contains the data to be loaded, then specify an asterisk (*). This specification is described in Identifying Data in the Control File with BEGINDATA .
Note:
The information in this section applies only to primary data files. It does not apply to LOBFILEs or SDFs.
For information about LOBFILES, see Loading LOB Data from LOBFILEs.
For information about SDFs, see Secondary Data Files (SDFs).
The syntax for INFILE
is as follows:
Table 9-1 describes the parameters for the INFILE
keyword.
Table 9-1 Parameters for the INFILE Keyword
Parameter | Description |
---|---|
|
Specifies that a data file specification follows. |
|
Name of the file containing the data. The file name can contain wildcards. An asterisk (*) represents multiple characters and a question mark (?) represents a single character. For example: INFILE 'emp*.dat' INFILE 'm?emp.dat' Any spaces or punctuation marks in the file name must be enclosed in single quotation marks. See Specifying File Names and Object Names. |
|
If your data is in the control file itself, then use an asterisk instead of the file name. If you have data in the control file and in data files, then you must specify the asterisk first in order for the data to be read. |
|
This is the file-processing options string. It specifies the data file format. It also optimizes data file reads. The syntax used for this string is specific to your operating system. See Specifying Data File Format and Buffering. |
- Examples of INFILE Syntax
The following list shows different ways you can specifyINFILE
syntax. - Specifying Multiple Data Files
To load data from multiple data files in one SQL*Loader run, use anINFILE
clause for each data file.
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
sample
with a default extension of .dat:
INFILE sample
-
Data contained in a file named
datafile
.dat
with a full path specified:INFILE 'c:/topdir/subdir/datafile.dat'
Note:
File names that include spaces or punctuation marks must be enclosed in single quotation marks.
-
Data contained in any file of type
.dat
whose name begins withemp
:INFILE 'emp*.dat'
-
Data contained in any file of type .dat whose name begins with m, followed by any other single character, and ending in emp. For example, a file named myemp.dat would be included in the following:
INFILE 'm?emp.dat'
Specifying Multiple Data Files
To load data from multiple data files in one SQL*Loader run, use an INFILE
clause for each data file.
Data files 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 data file. In such a case, the separate bad files and discard files must be declared immediately after each data file name. For example, the following excerpt from a control file specifies four data files 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 file name and extensionmydat2.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 theDISCARDMAX
option is used, SQL*Loader assumes that a discard file is required and creates it with the default namemydat4.dsc
.
Specifying CSV Format Files
To direct SQL*Loader to access the data files as comma-separated-values format files, use the CSV
clause.
This assumes that the file is a stream record format file with the normal carriage return string (for example, \n
on UNIX or Linux operating systems and either \n
or \r\n
on Windows operating systems). Record terminators can be included (embedded) in data values. The syntax for the CSV
clause is as follows:
FIELDS CSV [WITH EMBEDDED|WITHOUT EMBEDDED] [FIELDS TERMINATED BY ','] [OPTIONALLY ENCLOSED BY '"']
The following are key points regarding the FIELDS
CSV
clause:
-
The SQL*Loader default is to not use the
FIELDS
CSV
clause. -
The
WITH
EMBEDDED
andWITHOUT
EMBEDDED
options specify whether record terminators are included (embedded) within any fields in the data. -
If
WITH
EMBEDDED
is used, then embedded record terminators must be enclosed, and intra-datafile parallelism is disabled for external table loads. -
The
TERMINATED BY ','
andOPTIONALLY ENCLOSED BY '"'
options are the defaults and do not have to be specified. You can override them with different termination and enclosure characters. -
When the
CSV
clause is used, only delimitable data types are allowed as control file fields. Delimitable data types includeCHAR
, datetime, interval, and numericEXTERNAL
. -
The
TERMINATED
BY
andENCLOSED
BY
clauses cannot be used at the field level when the CSV clause is specified. -
When the
CSV
clause is specified, normal SQL*Loader blank trimming is done by default. You can specifyPRESERVE
BLANKS
to avoid trimming of spaces. Or, you can use the SQL functionsLTRIM
andRTRIM
in the field specification to remove left and/or right spaces. -
When the
CSV
clause is specified, theINFILE *
clause in not allowed. This means that there cannot be any data included in the SQL*Loader control file.
The following sample SQL*Loader control file uses the FIELDS
CSV
clause with the default delimiters:
LOAD DATA INFILE "mydata.dat" TRUNCATE INTO TABLE mytable FIELDS CSV WITH EMBEDDED TRAILING NULLCOLS ( c0 char, c1 char, c2 char, )
Identifying Data in the Control File with BEGINDATA
Specify the BEGINDATA
statement before the first data record.
If the data is included in the control file itself, then the INFILE
clause is followed by an asterisk rather than a file name. The actual data is placed in the control file after the load configuration specifications.
The syntax is:
BEGINDATA
first_data_record
Keep the following points in mind when using the BEGINDATA
statement:
-
If you omit the
BEGINDATA
statement but include data in the control file, then SQL*Loader tries to interpret your data as control information and issues an error message. If your data is in a separate file, then do not use theBEGINDATA
statement. -
Do not use spaces or other characters on the same line as the
BEGINDATA
statement, or the line containingBEGINDATA
will be interpreted as the first line of data. -
Do not put comments after
BEGINDATA,
or they will also be interpreted as data.See Also:
-
Specifying Data Files for an explanation of using
INFILE
-
Case study 1, Loading Variable-Length Data (see SQL*Loader Case Studies for information on how to access case studies)
-
Specifying Data File 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:
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"
Note:
This example uses the recommended convention of single quotation marks for file names and double quotation marks for everything else.
See Also:
Oracle Database Platform Guide for Microsoft Windows for information about using the os_file_proc_clause
on Windows systems.
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 caused Oracle errors.
If you have specified that a bad file is to be created, then the following applies:
-
If one or more records are rejected, then the bad file is created and the rejected records are logged.
-
If no records are rejected, then the bad file is not created.
-
If the bad file is created, then it overwrites any existing file with the same name; ensure that you do not overwrite a file you want to retain.
Note:
On some systems, a new version of the file may be created if a file with the same name already exists.
To specify the name of the bad file, use the BADFILE
clause. You can also specify the bad file from the command line with the BAD
parameter described in Command-Line Parameters for SQL*Loader.
A file name specified on the command line is associated with the first INFILE
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 data file so that you can reload the data after you correct it. For data files in stream record format, the record terminator that is found in the data file is also used in the bad file.
The syntax for the BADFILE
clause is as follows:
The BADFILE
clause specifies that a directory path or file name, or both, for the bad file follows. If you specify BADFILE
, then you must supply either a directory path or a file name, or both.
The directory
parameter specifies a directory path to which the bad file will be written.
The filename
parameter specifies a valid file name specification for your platform. Any spaces or punctuation marks in the file name must be enclosed in single quotation marks. If you do not specify a name for the bad file, then the name defaults to the name of the data file with an extension or file type of .bad.
- Examples of Specifying a Bad File Name
Using the bad file in an example. - 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. - Criteria for Rejected Records
This section explains the criteria for rejecting records.
Examples of Specifying a Bad File Name
Using the bad file in an example.
To specify a bad file with file name sample
and default file extension or file type of .bad,
enter the following in the control file:
BADFILE sample
To specify only a directory name, enter the following in the control file:
BADFILE '/mydisk/bad_dir/'
To specify a bad file with file name bad0001
and file extension or file type of .rej
, enter either of the following lines in the control file:
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, then 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
This section explains the criteria for rejecting records.
A record can be rejected for the following reasons:
-
Upon insertion, the record causes an Oracle error (such as invalid data for a given data type).
-
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.
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.
In a conventional path load, if the data file has a record that is being loaded into multiple tables and that record is rejected from at least one of the tables, then that record is not loaded into any of the tables.
The log file indicates the Oracle error for each rejected record. Case study 4 demonstrates rejected records. (See SQL*Loader Case Studies for information on how to access case studies.)
Specifying the Discard File
During execution, SQL*Loader 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 file name and one or more records fail to satisfy all of the
WHEN
clauses specified in the control file. (Be aware that if the discard file is created, then it overwrites any existing file with the same name.) -
If no records are discarded, then a discard file is not created.
You can specify the discard file from within the control file either by specifying its directory, or name, or both, or by specifying the maximum number of discards. Any of the following clauses result in a discard file being created, if necessary:
-
DISCARDFILE=[[directory/][filename]]
-
DISCARDS
-
DISCARDMAX
The discard file is created in the same record and file format as the data file. For data files in stream record format, the same record terminator that is found in the data file is also used in the discard file.
You can also create a discard file from the command line by specifying either the DISCARD
or DISCARDMAX
parameter. See SQL*Loader Command-Line Reference.
If no discard clauses are included in the control file or on the command line, then a discard file is not created even if there are discarded records (that is, records that fail to satisfy all of the WHEN
clauses specified in the control file).
- Specifying the Discard File in the Control File
To specify the name of the file, use theDISCARDFILE
clause, followed by a directory path and/or file name. - Examples of Specifying a Discard File Name
The list shows different ways that you can specify a name for the discard file from within the control file. - Criteria for Discarded Records
If there is noINTO TABLE
clause specified for a record, then the record is discarded. - 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. - Specifying the Discard File from the Command Line
This section explains how to specify a discard file from the command line.
Specifying the Discard File in the Control File
To specify the name of the file, use the DISCARDFILE
clause, followed by a directory path and/or file name.
The DISCARDFILE
clause specifies that a discard directory path and/or file name follows. Neither the directory_path
nor the filename
is required. However, you must specify at least one.
The directory
parameter specifies a directory to which the discard file will be written.
The filename
parameter specifies a valid file name specification for your platform. Any spaces or punctuation marks in the file name must be enclosed in single quotation marks.
The default file name is the name of the data file, and the default file extension or file type is .dsc
. A discard file name specified on the command line overrides one specified in the control file. If a discard file with that name already exists, then it is either overwritten or a new version is created, depending on your operating system.
- Limiting the Number of Discard Records
You can limit the number of records to be discarded for each data file by specifying aninteger
for either theDISCARDS
orDISCARDMAX
keyword.
Limiting the Number of Discard Records
You can limit the number of records to be discarded for each data file by specifying an integer
for either the DISCARDS
or DISCARDMAX
keyword.
You can specify a different number of discards for each data file. Or, if you specify the number of discards only once, then the maximum number of discards specified applies to all files.
When the discard limit is reached, processing of the data file terminates and continues with the next data file, if one exists.
If you specify a maximum number of discards, but no discard file name, then SQL*Loader creates a discard file with the default file name and file extension or file type.
Examples of Specifying a Discard File Name
The list shows different ways that you can specify a name for the discard file from within the control file.
-
To specify a discard file with file name
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, then 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.
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, provides an example of using a discard file. (See SQL*Loader Case Studies for information on how to access case studies.)
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.
Specifying the Discard File from the Command Line
This section explains how to specify a discard file from the command line.
See DISCARD for information about how to specify a discard file from the command line.
A file name specified on the command line overrides any discard file that you may have specified in the control file.
Specifying a NULLIF Clause At the Table Level
You can specify a NULLIF
clause at the table level.
The syntax is as follows:
NULLIF {=|!=}{"char_string"|x'hex_string'|BLANKS}
The char_string
and hex_string
values must be enclosed in either single quotation marks or double quotation marks.
This specification is used for each mapped character field unless a NULLIF
clause is specified at the field level. A NULLIF
clause specified at the field level overrides a NULLIF
clause specified at the table level.
SQL*Loader checks the specified value against the value of the field in the record. If there is a match using the equal or not equal specification, then the field is set to NULL for that row. Any field that has a length of 0 after blank trimming is also set to NULL.
If you do not want the default NULLIF
or any other NULLIF
clause applied to a field, you can specify NO
NULLIF
at the field level.
See Also:
-
Using the WHEN_ NULLIF_ and DEFAULTIF Clauses for more information about specifying a NULLIF clause at the field level
Specifying Datetime Formats At the Table Level
You can specify certain datetime formats at the table level in a SQL*Loader control file.
The syntax for each is as follows:
DATE FORMAT mask TIMESTAMP FORMAT mask TIMESTAMP WITH TIME ZONE mask TIMESTAMP WITH LOCAL TIME ZONE mask
This specification is used for every date or timestamp field unless a different mask is specified at the field level. A mask specified at the field level overrides a mask specified at the table level.
The following is an example of using the DATE
FORMAT
clause in a SQL*Loader control file. The DATE
FORMAT
clause is overridden by DATE
at the field level for the hiredate and entrydate fields:
LOAD DATA INFILE myfile.dat APPEND INTO TABLE EMP FIELDS TERMINATED BY "," DATE FORMAT "DD-Month-YYYY" (empno, ename, job, mgr, hiredate DATE, sal, comm, deptno, entrydate DATE)
See Also:
-
Datetime and Interval Data Types for information about specifying datetime data types at the field level
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.
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. - Unicode Character Sets
SQL*Loader supports loading data that is in a Unicode character set. - Database Character Sets
The Oracle database uses the database character set for data stored in SQLCHAR
data types (CHAR,
VARCHAR2,
CLOB,
andLONG
), for identifiers such as table names, and for SQL statements and PL/SQL source code. - Data File Character Sets
By default, the data file is in the character set defined by theNLS_LANG
parameter. - Input Character Conversion
The default character set for all data files, if theCHARACTERSET
parameter is not specified, is the session character set defined by theNLS_LANG
parameter. - Shift-sensitive Character Data
In general, loading shift-sensitive character data can be much slower than loading simple ASCII or EBCDIC data.
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.
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 (see SQL*Loader Case Studies for information on how to access case studies)
-
Oracle Database Globalization Support Guide for more information about Unicode encoding
Database Character Sets
The Oracle database uses the database character set for data stored in SQL CHAR
data types (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
data types (NCHAR,
NVARCHAR2,
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.
Data File Character Sets
By default, the data file is in the character set defined by the NLS_LANG
parameter.
The data file 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 data file (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 data file. SQL*Loader also supports UTF-16 encoding with little-endian byte ordering. However, the Oracle database 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.
The character set of the data file 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 data files, if the CHARACTERSET
parameter is not specified, is the session character set defined by the NLS_LANG
parameter.
The character set used in input data files can be specified with the CHARACTERSET
parameter.
SQL*Loader can automatically convert data from the data file 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 data file 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, then 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 also by 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.
- Considerations When Loading Data into VARRAYs or Primary-Key-Based REFs
This section describes the considerations that you should take when loading data intoVARRAY
s or into a primary-key-basedREF
s. - CHARACTERSET Parameter
Specifying theCHARACTERSET
parameter tells SQL*Loader the character set of the input data file. - Control File Character Set
The SQL*Loader control file itself is assumed to be in the character set specified for your session by theNLS_LANG
parameter. - Character-Length Semantics
Byte-length semantics are the default for all data files except those that use the UTF16 character set (which uses character-length semantics by default).
Considerations When Loading Data into VARRAYs or Primary-Key-Based REFs
This section describes the considerations that you should take when loading data into VARRAY
s or into a primary-key-based REF
s.
If you use SQL*Loader conventional path or the Oracle Call Interface (OCI) to load data into VARRAY
s or into primary-key-based REF
s, and the data being loaded is in a different character set than the database character set, then problems such as the following might occur:
-
Rows might be rejected because a field is too large for the database column, but in reality the field is not too large.
-
A load might be abnormally terminated without any rows being loaded, when only the field that really was too large should have been rejected.
-
Rows might be reported as loaded correctly, but the primary-key-based
REF
columns are returned as blank when they are selected with SQL*Plus.
To avoid these problems, set the client character set (using the NLS_LANG
environment variable) to the database character set before you load the data.
CHARACTERSET Parameter
Specifying the CHARACTERSET
parameter tells SQL*Loader the character set of the input data file.
The default character set for all data files, if the CHARACTERSET
parameter is not specified, is the session character set defined by the NLS_LANG
parameter. Only character data (fields in the SQL*Loader data types CHAR,
VARCHAR,
VARCHARC,
numeric EXTERNAL
, and the datetime and interval data types) is affected by the character set of the data file.
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 data file, the data in the data file 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 data file that has little-endian byte order, then SQL*Loader issues a warning message and processes the data file as little-endian.
The CHARACTERSET
parameter can be specified for primary data files and also for LOBFILEs and SDFs. All primary data files are assumed to be in the same character set. A CHARACTERSET
parameter specified before the INFILE
parameter applies to the entire list of primary data files. If the CHARACTERSET
parameter is specified for primary data files, then 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 specified with the INFILE
clause in the control file. The control file is always processed using the character set specified for your session by the NLS_LANG
parameter. Therefore, 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 data file.
See Also:
-
Oracle Database Globalization Support Guide for more information about the names of the supported character sets
-
Case study 11, Loading Data in the Unicode Character Set, for an example of loading a data file that contains little-endian UTF-16 encoded data. (See SQL*Loader Case Studies for information on how to access case studies.)
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 data file character set, then 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 data file 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 data file in the UTF-16 Unicode encoding, then 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 data files 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.
For the SQL*Loader data types (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 data file uses a single-byte character set. However, they are often different if the data file 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 data file and the target database columns.
Character-Length Semantics
Byte-length semantics are the default for all data files 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:
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 data files and also to LOBFILEs and secondary data files (SDFs). A LENGTH
specification before the INFILE
parameters applies to the entire list of primary data files. The LENGTH
specification specified for the primary data file 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 data file, then the following SQL*Loader data types will use character-length semantics:
-
CHAR
-
VARCHAR
-
VARCHARC
-
DATE
-
EXTERNAL
numerics (INTEGER
,FLOAT
,DECIMAL
, andZONED
)
For the VARCHAR
data type, the length subfield is still a binary SMALLINT
length subfield, but its value indicates the length of the character string in characters.
The following data types use byte-length semantics even if character-length semantics are being used for the data file, 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 data file. This is necessary to handle data files that have a mix of data of different data types, 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
data type, 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 data file can be used independent of whether character-length semantics are used for the database columns. Therefore, the data file and the database columns can use either the same or different length semantics.
Shift-sensitive Character Data
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, then 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.
Interrupted Loads
Loads are interrupted and discontinued for several 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 data file, or a Ctrl+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.
- Discontinued Conventional Path Loads
In a conventional path load, data is committed after all data in the bind array is loaded into all tables. - Discontinued Direct Path Loads
In a direct path load, the behavior of a discontinued load varies depending on the reason the load was discontinued. - 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. - 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 data file. - 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.
See Also:
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, then 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.
These sections describe the reasons why a load was discontinued:
- Load Discontinued Because of Space Errors
If a load is discontinued because of space errors, then the behavior of SQL*Loader depends on whether you are loading data into multiple subpartitions. - Load Discontinued Because Maximum Number of Errors Exceeded
If the maximum number of errors is exceeded, then SQL*Loader stops loading records into any table and the work done to that point is committed. - Load Discontinued Because of Fatal Errors
If a fatal error is encountered, then the load is stopped and no data is saved unlessROWS
was specified at the beginning of the load. - Load Discontinued Because a Ctrl+C Was Issued
If SQL*Loader is in the middle of saving data when a Ctrl+C is issued, then it continues to do the save and then stops the load after the save completes.
Load Discontinued Because of Space Errors
If a load is discontinued because of space errors, then the behavior of SQL*Loader depends on whether you are loading data into multiple subpartitions.
-
Space errors when loading data into multiple subpartitions (that is, loading into a partitioned table, a composite partitioned table, or one partition of a composite partitioned table):
If space errors occur when loading into multiple subpartitions, then the load is discontinued and no data is saved unless
ROWS
has been specified (in which case, all data that was previously committed will be saved). The reason for this behavior is that it is possible rows might be loaded out of order. This is because each row is assigned (not necessarily in order) to a partition and each partition is loaded separately. If the load discontinues before all rows assigned to partitions are loaded, then the row for record "n" may have been loaded, but not the row for record "n-1". Therefore, the load cannot be continued by simply usingSKIP=N
.
-
Space errors when loading data into an unpartitioned table, one partition of a partitioned table, or one subpartition of a composite partitioned table:
If there is one
INTO TABLE
statement in the control file, then SQL*Loader commits as many rows as were loaded before the error occurred.If there are multiple
INTO TABLE
statements in the control file, then SQL*Loader loads data already read from the data file into other tables and then commits the data.In either case, this behavior is independent of whether the
ROWS
parameter was specified. When you continue the load, you can use theSKIP
parameter to skip rows that have already been loaded. In the case of multipleINTO TABLE
statements, a different number of rows could have been loaded into each table, so to continue the load you would need to specify a different value for theSKIP
parameter for every table. SQL*Loader only reports the value for theSKIP
parameter if it is the same for all tables.
Load Discontinued Because Maximum Number of Errors Exceeded
If the maximum number of errors is exceeded, then 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 reports the value for the SKIP
parameter only if it is the same for all tables.
Load Discontinued Because of Fatal Errors
If a fatal error is encountered, then 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 reports the value for the SKIP
parameter only if it is the same for all tables.
Load Discontinued Because a Ctrl+C Was Issued
If SQL*Loader is in the middle of saving data when a Ctrl+C is issued, then 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 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, then all indexes are left in a valid state.
If the direct path load method is used, then any indexes on the table are left in an unusable state. You can either rebuild or re-create the indexes before continuing, or after the load is restarted and completes.
Other indexes are valid if no other errors occurred. See Indexes Left in an Unusable State 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 data file.
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:
Assembling Logical Records from Physical Records
This section describes assembling logical records from physical records.
To combine multiple physical records into one logical record, you can use one of the following clauses, depending on your data:
-
CONCATENATE
-
CONTINUEIF
- Using CONCATENATE to Assemble Logical Records
UseCONCATENATE
when you want SQL*Loader to always combine the same number of physical records to form one logical record. - Using CONTINUEIF to Assemble Logical Records
UseCONTINUEIF
if the number of physical records to be combined varies.
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. In direct path loads, the default value for COLUMNARRAYROWS
is large, so 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.
Using CONTINUEIF to Assemble Logical Records
Use CONTINUEIF
if the number of physical records to be combined varies.
The CONTINUEIF
clause 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, then the second record would not be added to the first.
The full syntax for CONTINUEIF
adds even more flexibility:
Table 9-2 describes the parameters for the CONTINUEIF
clause.
Table 9-2 Parameters for the CONTINUEIF Clause
Parameter | 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. |
|
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 (!= or <>). For the equal operator, the field and comparison string must match exactly for the condition to be true. For the not equal operator, they can differ in any character. |
|
This test is similar to
|
|
Specifies the starting and ending column numbers in the physical record. Column numbers start with 1. Either a hyphen or a colon is acceptable ( If you omit |
|
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 |
|
Includes ' |
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.
For CONTINUEIF
THIS
and CONTINUEIF
LAST
, if the PRESERVE
parameter is not specified, then 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. For example, if CONTINUEIF
THIS(3:5)='***'
is specified, then positions 3
through 5
are removed from all records. This means that the continuation characters are removed if they are in positions 3
through 5
of the record. It also means that the characters in positions 3
through 5
are removed from the record even if the continuation characters are not in positions 3
through 5
.
For CONTINUEIF
THIS
and CONTINUEIF
LAST
, if the PRESERVE
parameter is used, then the continuation field is kept in all physical records when the logical record is assembled.
CONTINUEIF
LAST
differs from CONTINUEIF
THIS
and CONTINUEIF
NEXT
. For CONTINUEIF
LAST
, where the positions of the continuation field vary from record to record, the continuation field is never removed, even if PRESERVE
is not specified.
Example 9-3 through Example 9-6 show the use of CONTINUEIF THIS
and CONTINUEIF NEXT,
with and without the PRESERVE
parameter.
Example 9-3 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 9-4 CONTINUEIF THIS with the PRESERVE Parameter
Assume that you have the same physical records as in Example 9-3.
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 9-5 CONTINUEIF NEXT 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 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 9-3).
aaaaaaaa....bbbbbbbb....cccccccc.... dddddddddd..eeeeeeeeee..ffffffffff..
Example 9-6 CONTINUEIF NEXT with the PRESERVE Parameter
Assume that you have the same physical records as in Example 9-5.
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, for an example of the CONTINUEIF
clause. (See SQL*Loader Case Studies for information on how to access case studies.)
Loading Logical Records into Tables
This section describes 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
- Specifying Table Names
TheINTO
TABLE
clause of theLOAD
DATA
statement enables you to identify tables, fields, and data types. - Table-Specific Loading Method
When you are loading a table, you can use theINTO
TABLE
clause to specify a table-specific loading method (INSERT
,APPEND
,REPLACE
, orTRUNCATE
) that applies only to that table. - Table-Specific OPTIONS Parameter
TheOPTIONS
parameter can be specified for individual tables in a parallel load. (It is valid only for a parallel load.) - Loading Records Based on a Condition
You can choose to load or discard a logical record by using theWHEN
clause to test a condition in the record. - Specifying Default Data Delimiters
If all data fields are terminated similarly in the data file, then you can use theFIELDS
clause to indicate the default termination and enclosure delimiters. - 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.
Specifying Table Names
The INTO
TABLE
clause of the LOAD
DATA
statement enables you to identify tables, fields, and data types.
It defines the relationship between records in the data file and tables in the database. The specification of fields and data types is described in later sections.
- INTO TABLE Clause
Among its many functions, theINTO
TABLE
clause enables you to specify the table into which you load data.
INTO TABLE Clause
Among its many functions, the INTO
TABLE
clause enables you to specify the table into which you load data.
To load multiple tables, you include one INTO
TABLE
clause for each table you want 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:
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
refers to the table emp
in the scott
schema).
Note:
SQL*Loader considers the default schema to be whatever schema is current after your connect to the database finishes executing. This means that the default schema will not necessarily be the one you specified in the connect string, if there are logon triggers present that get executed during connection to a database.
If you have a logon trigger that changes your current schema to a different one when you connect to a certain database, then SQL*Loader uses that new schema as the default.
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 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
This section describes how to load data into empty tables. - Loading Data into Nonempty Tables
This section describes loading data into nonempty tables.
Loading Data into Empty Tables
This section describes how to load data into empty tables.
If the tables you are loading into are empty, then 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, provides an example. (See SQL*Loader Case Studies for information on how to access case studies.)
Loading Data into Nonempty Tables
This section describes loading data into nonempty tables.
If the tables you are loading into already contain data, then you have three options:
-
APPEND
-
REPLACE
-
TRUNCATE
Note:
When
REPLACE
orTRUNCATE
is specified, the entire table is replaced, not just individual rows. After the rows are successfully deleted, aCOMMIT
statement 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.
APPEND
If data already exists in the table, then SQL*Loader appends the new rows to it. If data does not already exist, then 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, provides an example. (See SQL*Loader Case Studies for information on how to access case studies.)
REPLACE
The REPLACE
option executes a SQL DELETE FROM TABLE
statement. 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, provides an example. (See SQL*Loader Case Studies for information on how to access case studies.)
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 about cascaded deletes, see Oracle 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:
- Load your data into a work table.
- Use the SQL
UPDATE
statement with correlated subqueries. - Drop the work table.
TRUNCATE
The TRUNCATE
option executes a SQL TRUNCATE TABLE
table_name
REUSE STORAGE
statement, which means that the table's extents will be reused. The TRUNCATE
option 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, then 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.
Table-Specific OPTIONS Parameter
The OPTIONS
parameter can be specified for individual tables in a parallel load. (It is valid only for a parallel load.)
The syntax for the OPTIONS
parameter is as follows:
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:
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')
- Using the WHEN Clause with LOBFILEs and SDFs
This section describes using the WHEN clause with LOBFILEs and SDFs.
See Also:
-
Using the WHEN_ NULLIF_ and DEFAULTIF Clauses for information about how SQL*Loader evaluates
WHEN
clauses, as opposed toNULLIF
andDEFAULTIF
clauses -
Case study 5, Loading Data into Multiple Tables, for an example of using the
WHEN
clause (see "SQL*Loader Case Studies" for information on how to access case studies)
Specifying Default Data Delimiters
If all data fields are terminated similarly in the data file, then you can use the FIELDS
clause to indicate the default termination and enclosure delimiters.
termination_spec
Note:
Terminator strings can contain one or more characters. Also, TERMINATED BY EOF
applies only to loading LOBs from a LOBFILE.
enclosure_spec
Note:
Enclosure strings can contain one or more characters.
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, provides an example. (See SQL*Loader Case Studies for information on how to access case studies.)
See Also:
-
Specifying Delimiters for a complete description of the syntax
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.
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:
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, for an example of using TRAILING NULLCOLS
(see SQL*Loader Case Studies for information on how to access case studies)
Index Options
This section describes 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:
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 operation, the original index, the new index, and the space for new entries all simultaneously occupy storage space.
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
These sections describe the benefits of using multiple INTO TABLE clauses.
Multiple INTO
TABLE
clauses enable 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 of using fixed field locations or the POSITION
parameter.
- Extracting Multiple Logical Records
When the data records are short, more than one can be stored in a single, physical record to use the storage space efficiently. - Distinguishing Different Input Record Formats
A single data file might contain records in a variety of formats. - Distinguishing Different Input Row Object Subtypes
A single data file may contain records made up of row objects inherited from the same base row object type. - Loading Data into Multiple Tables
By using thePOSITION
parameter with multipleINTO TABLE
clauses, data from a single record can be loaded into multiple normalized tables. - Summary of Using Multiple INTO TABLE Clauses
MultipleINTO TABLE
clauses allow you to extract multiple logical records from a single input record and recognize different record formats in the same file.
Extracting Multiple Logical Records
When the data records are short, more than one can be stored in a single, physical record to use the storage space efficiently.
Some data storage and transfer media have fixed-length physical records.
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 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.
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 and in Loading Data into Multiple Tables.
Distinguishing Different Input Record Formats
A single data file 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
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
Records can be loaded as delimited data.
Relative Positioning Based on the POSITION Parameter
Records can be loaded as delimited data.
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 data file may contain records made up of row objects inherited from the same base row object type.
For example, consider the following simple object type and object table definitions, in which a nonfinal base object type is defined along with two object subtypes that inherit their row objects 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 data file 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.
Note:
Multiple subtypes cannot be loaded with the same INTO
TABLE
statement. Instead, you must use multiple INTO
TABLE
statements and have each one load a different subtype.
INTO TABLE persons 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 for more information about loading object types
Loading Data into Multiple Tables
By using the POSITION
parameter 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, for an example. (See SQL*Loader Case Studies for information about how to access case studies.).
Summary of Using Multiple INTO TABLE Clauses
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.
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
Multiple rows are read at one time and stored in the bind array.
SQL*Loader uses the SQL array-interface option to transfer data to the database. 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
statement is issued.
The determination of bind array size pertains to SQL*Loader's conventional path option. In general, it does not apply to the direct path load method because a direct path load uses the direct path API. However, the bind array might be used for special cases of direct path load where data conversion is necessary.
- Size Requirements for Bind Arrays
The bind array must be large enough to contain a single row. - Performance Implications of Bind Arrays
Large bind arrays minimize the number of calls to the Oracle database and maximize performance. - Specifying Number of Rows Versus Size of Bind Array
When you specify a bind array size using the command-line parameterBINDSIZE
or theOPTIONS
clause in the control file, you impose an upper limit on the bind array. - 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. - Minimizing Memory Requirements for Bind Arrays
Pay particular attention to the default sizes allocated forVARCHAR
,VARGRAPHIC
, and the delimited forms ofCHAR
,DATE
, and numericEXTERNAL
fields. - Calculating Bind Array Size for Multiple INTO TABLE Clauses
When calculating a bind array size for a control file that has multipleINTO
TABLE
clauses, calculate as if theINTO
TABLE
clauses were not present.
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, then 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 maximum value for ROWS
in a conventional path load is 65534.)
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, then SQL*Loader generates an error.
Performance Implications of Bind Arrays
Large bind arrays minimize the number of calls to the Oracle database 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.
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
or the OPTIONS
clause in the control file, 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, then 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
or the OPTIONS
clause in the control file.
If that size fits within the bind array maximum, then 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, then 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, then 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 equals 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 bytes, as described in SQL*Loader Data Types. 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 data types is described in SQL*Loader Data Types. 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 data types (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 data types 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 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
Use the control file to determine the size of the length indicator. - Calculating the Size of Field Buffers
This section describes how to calculate the size of the field buffers.
Determining the Size of the Length Indicator
Use the control file to determine 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
This section describes how to calculate the size of the field buffers.
Table 9-3 through Table 9-6 summarize the memory requirements for each data type. "L" is the length specified in the control file. "P" is precision. "S" is the size of the length indicator. For more information about these values, see SQL*Loader Data Types.
Table 9-3 Fixed-Length Fields
Data Type | Size in Bytes (Operating System-Dependent) |
---|---|
|
The size of the |
|
|
|
The size of |
|
The size of the |
|
The size of the |
|
The size of |
|
The size of |
|
The size of |
|
Composed of 2 numbers. The first specifies length, and the second (which is optional) specifies |
|
This data type is for |
Table 9-4 Nongraphic Fields
Data Type | Default Size | Specified Size |
---|---|---|
(packed) |
None |
(N+1)/2, rounded up |
|
None |
P |
|
None |
L |
|
1 |
L + S |
datetime and interval (no delimiters) |
None |
L + S |
numeric |
None |
L + S |
Table 9-5 Graphic Fields
Data Type | Default Size | Length Specified with POSITION | Length Specified with DATA TYPE |
---|---|---|---|
|
None |
L |
2*L |
|
None |
L - 2 |
2*(L-2) |
|
4KB*2 |
L+S |
(2*L)+S |
Table 9-6 Variable-Length Fields
Data Type | Default Size | Maximum Length Specified (L) |
---|---|---|
|
4 KB |
L+S |
|
255 |
L+S |
datetime and interval (delimited) |
255 |
L+S |
numeric |
255 |
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 data file 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 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, then 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.