55 DBMS_LOGMNR_D

Using DBMS_LOGMNR_D

This section contains the following topics, which relate to using the DBMS_LOGMNR_D package:

• Overview

• Security Model

Overview

LogMiner requires a dictionary to translate object IDs into object names when it returns redo data to you. LogMiner gives you three options for supplying the dictionary:

• Using the online catalog

• Extracting a LogMiner dictionary to the redo log files

• Extracting a LogMiner dictionary to a flat file

Use the BUILD procedure to extract the LogMiner dictionary to the redo log files or a flat file. If you want to specify the online catalog as the dictionary source, you do so when you start LogMiner with the DBMS_LOGMNR.START_LOGMNR package.

Use the SET_TABLESPACE procedure if you want LogMiner tables to use a tablespace other than the default SYSAUX tablespace.

Security Model

You must have the EXECUTE_CATALOG_ROLE role to use the DBMS_LOGMNR_D package.

Summary of DBMS_LOGMNR_D Subprograms

BUILD Procedure

This procedure extracts the LogMiner data dictionary to either the redo log files or to a flat file.

Syntax

DBMS_LOGMNR_D.BUILD (
     dictionary_filename  IN  VARCHAR2,
     dictionary_location  IN  VARCHAR2,
     options              IN  NUMBER);

Parameters

Exceptions

Usage Notes

• To extract the LogMiner dictionary to a flat file, you must supply a filename and location.

  To extract the LogMiner dictionary to the redo log files, specify only the STORE_IN_REDO_LOGS option. The size of the LogMiner dictionary may cause it to be contained in multiple redo log files.

  The combinations of parameters used result in the following behavior:

  • If you do not specify any parameters, an error is returned.

  • If you specify a filename and location, without any options, the LogMiner dictionary is extracted to a flat file with that name.

  • If you specify a filename and location, as well as the STORE_IN_FLAT_FILE option, the LogMiner dictionary is extracted to a flat file with the specified name.

  • If you do not specify a filename and location, but do specify the STORE_IN_REDO_LOGS option, the LogMiner dictionary is extracted to the redo log files.

  • If you specify a filename and location, as well as the STORE_IN_REDO_LOGS option, an error is returned.

  • If you do not specify a filename and location, but do specify the STORE_IN_FLAT_FILE option, an error is returned.

• Ideally, the LogMiner dictionary file will be created after all database dictionary changes have been made and prior to the creation of any redo log files that are to be analyzed. As of Oracle9i release 1 (9.0.1), you can use LogMiner to dump the LogMiner dictionary to the redo log files or a flat file, perform DDL operations, and dynamically apply the DDL changes to the LogMiner dictionary.

• Do not run the DBMS_LOGMNR_D.BUILD procedure if there are any ongoing DDL operations.

• The database must be open when you run the DBMS_LOGMNR_D.BUILD procedure.

• When extracting a LogMiner dictionary to a flat file, the procedure queries the dictionary tables of the current database and creates a text-based file containing the contents of the tables. To extract a LogMiner dictionary to a flat file, the following conditions must be met:

  • You must specify a directory for use by the PL/SQL procedure. To do so, set the initialization parameter UTL_FILE_DIR in the initialization parameter file. For example:

    UTL_FILE_DIR = /oracle/dictionary
    

    After setting the parameter, you must shut down and restart the database for this parameter to take effect. If you do not set this parameter, the procedure will fail.

  • You must ensure that no DDL operations occur while the LogMiner dictionary build is running. Otherwise, the LogMiner dictionary file may not contain a consistent snapshot of the database dictionary.

  Be aware that the DDL_DICT_TRACKING option to the DBMS_LOGMNR.START_LOGMNR procedure is not supported for flat file dictionaries created prior to Oracle9i. If you attempt to use the DDL_DICT_TRACKING option with a LogMiner database extracted to a flat file prior to Oracle9i, the ORA-01330 error (problem loading a required build table) is returned.

• To extract a LogMiner dictionary file to the redo log files, the following conditions must be met:

  • The DBMS_LOGMNR_D.BUILD procedure must be run on a system that is running Oracle9i or later.

  • Archivelog mode must be enabled in order to generate usable redo log files.

  • The COMPATIBLE parameter in the initialization parameter file must be set to 9.2.0 or higher.

  • The database to which LogMiner is attached must be Oracle9i or later.

  In addition, supplemental logging (at least the minimum level) should be enabled to ensure that you can take advantage of all the features that LogMiner offers. See Oracle Database Utilities for information about using supplemental logging with LogMiner.

Examples

Example 1: Extracting the LogMiner Dictionary to a Flat File

The following example extracts the LogMiner dictionary file to a flat file named dictionary.ora in a specified path (/oracle/database).

SQL> EXECUTE dbms_logmnr_d.build('dictionary.ora', - 
     '/oracle/database/', -
     options => dbms_logmnr_d.store_in_flat_file);

Example 2: Extracting the LogMiner Dictionary to the Redo Log Files

The following example extracts the LogMiner dictionary to the redo log files.

SQL> EXECUTE dbms_logmnr_d.build( -
     options => dbms_logmnr_d.store_in_redo_logs);

SET_TABLESPACE Procedure

By default, all LogMiner tables are created to use the SYSAUX tablespace. However, it may be desirable to have LogMiner tables use an alternate tablespace. Use this procedure to move LogMiner tables to an alternate tablespace.

Syntax

DBMS_LOGMNR_D.SET_TABLESPACE (
     new_tablespace        IN VARCHAR2);

Parameters

Usage Notes

• Users upgrading from earlier versions of Oracle Database may find LogMiner tables in the SYSTEM tablespace. Oracle encourages such users to consider using the SET_TABLESPACE procedure to move the tables to the SYSAUX tablespace once they are confident that they will not be downgrading to an earlier version of Oracle Database.

• Users of this routine must supply an existing tablespace.

  See Also:

  Oracle Database Concepts and Oracle Database SQL Reference for information about tablespaces and how to create them

Example: Using the DBMS_LOGMNR_D.SET_TABLESPACE Procedure

The following example shows the creation of an alternate tablespace and execution of the DBMS_LOGMNR_D.SET_TABLESPACE procedure.

SQL> CREATE TABLESPACE  logmnrts$ datafile '/usr/oracle/dbs/logmnrts.f'
     SIZE 25 M REUSE AUTOEXTEND ON MAXSIZE UNLIMITED;

SQL> EXECUTE dbms_logmnr_d.set_tablespace('logmnrts$');