Oracle | DBMS

Oracle DBMS_LOGMNR and Log Mining Version 21c

General Information

Library Note

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Purpose Enables online query online of archived redo log files through a SQL interface and provides most of the tools required to start and stop log mining.

AUTHID DEFINER

Constants

Name	Data Type	Value
Add archive log option flags
NEW	BINARY_INTEGER	1
REMOVEFILE	BINARY_INTEGER	2
ADDFILE	BINARY_INTEGER	3
Status column option flags
VALID_SQL	BINARY_INTEGER	0
INVALID_SQL	BINARY_INTEGER	2
UNGUARANTEED_SQL	BINARY_INTEGER	3
CORRUPTED_BLK_IN_REDO	BINARY_INTEGER	4
ASSEMBLY_REQUIRED_SQL	BINARY_INTEGER	5
HOLE_IN_LOGSTREAM	BINARY_INTEGER	1291

Start LOGMNR option flags
Name	Data Type	Value	Description
COMMITTED_DATA_ONLY	BINARY_INTEGER	2	If set, DML statements corresponding to committed transactions are returned. DML statements corresponding to a committed transaction are grouped together. Transactions are returned in their commit order. Transactions that are rolled back or in-progress are filtered out, as are internal redo records (those related to index operations, management, and so on). If this option is not set, all rows for all transactions (committed, rolled back, and in-progress) are returned in the order in which they are found in the redo logs (in order of SCN values).
CONTINUOUS_MINE	BINARY_INTEGER	1024	Directs LogMiner to automatically add redo log files, as needed, to find the data of interest. You only need to specify the first log to start mining, or just the starting SCN or date to indicate to LogMiner where to begin mining logs. You are not required to specify any redo log files explicitly. LogMiner automatically adds and mines the (archived and online) redo log files for the data of interest. This option requires that LogMiner is connected to the same database instance that is generating the redo log files. It also requires that the database be mounted and that archiving be enabled. Beginning with Oracle Database release 10.1, the CONTINUOUS_MINE options is supported for use in an Oracle Real Application Clusters environment.
DDL_DICT_TRACKING	BINARY_INTEGER	8	If the LogMiner dictionary in use is a flat file or in the redo log files, LogMiner updates its internal dictionary if a DDL event occurs. This ensures that correct SQL_REDO and SQL_UNDO information is maintained for objects that are modified after the LogMiner internal dictionary is built. The database to which LogMiner is connected must be open. This option cannot be used in conjunction with the DICT_FROM_ONLINE_CATALOG option.
DICT_FROM_ONLINE_CATALOG	BINARY_INTEGER	16	Directs LogMiner to use the current online database dictionary rather than a LogMiner dictionary contained in a flat file or in the redo log files being analyzed. This option cannot be used in conjunction with the DDL_DICT_TRACKING option. The database to which LogMiner is connected must be the same one that generated the redo log files. Expect to see a value of 2 in the STATUS column of the GV$LOGMNR_CONTENTS view if the table definition in the database does not match the table definition in the redo log file.
DICT_FROM_REDO_LOGS	BINARY_INTEGER	32	If set, LogMiner expects to find a LogMiner dictionary in the redo log files that were specified. The redo log files are specified with the DBMS_LOGMNR.ADD_LOGFILE procedure or with the DBMS_LOGMNR.START_LOGMNR procedure with the CONTINUOUS_MINE option.
NO_DICT_RESET_ONSELECT	BINARY_INTEGER	1	Will be deprecated soon
NO_ROWID_IN_STMT	BINARY_INTEGER	2048	If set, the ROWID clause is not included in the reconstructed SQL statements. The redo log file may already contain logically unique identifiers for modified rows if supplemental logging is enabled. When using this option, you must be sure that supplemental logging was enabled in the source database at the appropriate level and that no duplicate rows exist in the tables of interest. LogMiner does not make any guarantee regarding the uniqueness of logical row identifiers.
NO_SQL_DELIMITER	BINARY_INTEGER	64	If set, the SQL delimiter (a semicolon) is not placed at the end of reconstructed SQL statements. This is helpful for applications that open a cursor and then execute the reconstructed statements.
PRINT_PRETTY_SQL	BINARY_INTEGER	512	If set, LogMiner formats the reconstructed SQL statements for ease of reading. These reconstructed SQL statements are not executable.
SKIP_CORRUPTION	BINARY_INTEGER	4	Directs a select operation on the GV$LOGMNR_CONTENTS view to skip any corruptions in the redo log file being analyzed and continue processing. This option works only when a block in the redo log file (and not the header of the redo log file) is corrupt. You should check the INFO column in the GV$LOGMNR_CONTENTS view to determine the corrupt blocks skipped by LogMiner. When a corruption in the redo log file is skipped, the OPERATION column contains the value CORRUPTED_BLOCKS, and the STATUS column contains the value 1343.
STRING_LITERALS_IN_STMT	BINARY_INTEGER	4096	Undocumented

Data Types SUBTYPE Length IS BINARY_INTEGER; SUBTYPE ThreadId IS BINARY_INTEGER; -- workarounds for the lack of constrained subtypes LogFileNameTemplate VARCHAR2(256); SUBTYPE LogFileName IS LogFileNameTemplate%TYPE; LogFileDescTemplate VARCHAR2(256); SUBTYPE LogFileDescription IS LogFileDescTemplate%TYPE;

Dependencies

DBA_LOGMNR_LOG	GV_$LOGMNR_CALLBACK	GV_$LOGMNR_PARAMETERS
DBA_LOGMNR_PURGED_LOG	GV_$LOGMNR_CONTENTS	GV_$LOGMNR_PROCESS
DBA_LOGMNR_SESSION	GV_$LOGMNR_DICTIONARY	GV_$LOGMNR_REGION
DBMS_APPLY_ADM_INTERNAL	GV_$LOGMNR_DICTIONARY_LOAD	GV_$LOGMNR_SESSION
DBMS_LOGMNR_INTERNAL	GV_$LOGMNR_LATCH	GV_$LOGMNR_STATS
DBMS_STREAMS_ADM_IVK	GV_$LOGMNR_LOGFILE	GV_$LOGMNR_TRANSACTION
DBMS_STREAMS_ADM_UTL	GV_$LOGMNR_LOGS

Documented Yes: Packages and Types Reference

Exceptions

Error Code	Reason
ORA-00904	Value specified for the column_name parameter is not a fully qualified column name.
ORA-01281	startScn or endSCN parameter specified is not a valid SCN or endScn is greater then startScn
ORA-01282	startTime parameter not between years 1988 and 2110 or endTime parameter is greater than year 2110
ORA-01283	The value specified in the Options parameter is not a NUMBER or is not a known LogMiner Adhoc option
ORA-01284	Specified dictionary file in DictFileName parameter has a length greater then 256 or cannot be opened
ORA-01285	DictFileName parameter is not a valid VARCHAR2
ORA-01286	Options specified require start time or start SCN
ORA-01287	Specified file is from a different database incarnation
ORA-01289	Specified file has already been added to the list. Duplicate redo log files cannot be added.
ORA-01290	Specified file is not in the current list and therefore cannot be removed from the list.
ORA-01291	Redo files needed to satisfy the user's requested SCN/time range are missing. The user can specify ALLOW_MISSING_LOGS option. Missing logs are not allowed when DDL tracking is in use.
ORA-01292	No log file has been registered with LogMiner
ORA-01293	Mounted database required for options specified (CONTINUOUS_MINE)
ORA-01294	Error while processing the data dictionary extract
ORA-01295	DB_ID of the data dictionary does not match that of the redo logs
ORA-01296	Character set specified in the data dictionary does not match (is incompatible with) that of the database
ORA-01297	Redo version mismatch between the dictionary and the registered redo logs
ORA-01298	More than one dictionary source was specified or DDL_DICT_TRACKING was requested with DICT_FROM_ONLINE_CATALOG
ORA-01299	Dictionary is from a different database incarnation
ORA-01300	Writable database required for options specified (DDL_DICT_TRACKING, DICT_FROM_REDO_LOGS, DICT_FROM_ONLINE_CATALOG)
ORA-01323	A LogMiner dictionary is not associated with the LogMiner session
ORA-01324	Specified file cannot be added to the list because there is a DB_ID mismatch.
ORA-01371	A logfile containing the dictionary dump to redo logs is missing

First Available 8.1.5

Pragmas pragma TIMESTAMP('1998-05-05:11:25:00');

Security Model Owned by SYS with EXECUTE granted to the EXECUTE_CATALOG_ROLE role

Source {ORACLE_HOME}/rdbms/admin/dbmslm.sql

Subprograms

ADD_LOGFILE	MINE_VALUE	REMOVE_LOGFILE
COLUMN_PRESENT	PROFILE	START_LOGMNR
END_LOGMNR

ADD_LOGFILE

Register log files to be analyzed dbms_logmnr.add_logfile( logfilename IN VARCHAR2, options IN BINARY_INTEGER DEFAULT ADDFILE);

See MINE_VALUE Demo Below

COLUMN_PRESENT

Call this function for any row returned from the V$LOGMNR_CONTENTS view to determine if undo or redo column values exist for the column specified by the column_name input parameter to this function -- designed to be used in conjunction with the MINE_VALUE function
dbms_logmnr.column_present( sql_redo_undo IN NUMBER DEFAULT 0, column_name IN VARCHAR2 DEFAULT '') RETURN BINARY_INTEGER;

See MINE_VALUE Demo Below

END_LOGMNR

Completes a log miner session dbms_logmnr.end_logmnr;

See MINE_VALUE Demo Below

MINE_VALUE

Facilitates queries based on a column's data value dbms_logmnr.mine_value( sql_redo_undo IN NUMBER DEFAULT 0, column_name IN VARCHAR2 DEFAULT '') RETURN VARCHAR2;

conn / as sysdba

      

      SHUTDOWN IMMEDIATE;

      

      STARTUP MOUNT;

      

      ALTER DATABASE ARCHIVELOG;

      

      ALTER DATABASE OPEN;

      

      GRANT select ON v_$logmnr_contents TO uwclass;

      

      desc gv$log

      

      SELECT group#, thread#, sequence#, members, status

      FROM v$log;

      

      ALTER SYSTEM switch logfile;

      

      SELECT group#, thread#, sequence#, members, status

      FROM gv$log;

      

      desc  v$logmnr_contents

      

      SELECT COUNT(*)

      FROM v$logmnr_contents;

      

      GRANT select ON v_$database TO uwclass;

      

      conn uwclass/uwclass

      

      -- capture starting SCN

      SELECT current_scn

      FROM v$database;

      
      -- 7466113

      

      UPDATE airplanes

      SET customer_id = 'FIND'

      WHERE line_number = 13397;

      

      COMMIT;

      

      -- capture ending SCN

      SELECT current_scn

      FROM v$database;

      -- 7466134

      

      ALTER SYSTEM switch logfile;

      

      -- copy control file to c:\temp\demo.arc

      

      exec sys.dbms_logmnr.add_logfile('c:\temp\demo1.arc');

      exec sys.dbms_logmnr.add_logfile('c:\temp\demo2.arc');

      exec sys.dbms_logmnr.add_logfile('c:\temp\demo3.arc');

      exec sys.dbms_logmnr.start_logmnr(7466113,7466134);

      
      

      exec sys.dbms_logmnr.start_logmnr(7466113, 7466134, options=>2);

      

      col object_name format a30

      

      desc  v$logmnr_contents;

      -- note abs_file#, rel_file#, data_blk#

      

      SELECT v.scn, v.commit_timestamp, v.table_name, o.object_name, v.operation

      FROM sys.v_$logmnr_contents v, dba_objects_ae o

      WHERE SUBSTR(v.table_name,6) = o.object_id;

      

      SELECT sql_redo

      FROM sys.v_$logmnr_contents;

      

      SELECT sql_undo

      FROM sys.v_$logmnr_contents;

      

      exec sys.dbms_logmnr.end_logmnr;

      

      conn / as sysdba

      

      SHUTDOWN IMMEDIATE;

      

      STARTUP MOUNT EXCLUSIVE;

      

      ALTER DATABASE NOARCHIVELOG;

      

      ALTER DATABASE OPEN;

      

      SELECT info

      FROM gv$logmnr_contents;

      

      SELECT sql_redo, sql_undo

      FROM gv$logmnr_contents

      WHERE username = 'UWCLASS';

      

      SELECT utl_raw.cast_to_varchar2(HEXTORAW('53414c')) FROM dual;

      NWO  HEXTORAW('4e574f')

      USAF HEXTORAW('55534146')

      DAL  HEXTORAW('44414c')

      SAL  HEXTORAW('53414c')

      

      SELECT sql_redo

      FROM sys.v_$logmnr_contents

      WHERE seg_name = 'AIRPLANES'

      AND seg_owner = 'UWCLASS'

      AND operation = 'UPDATE'

      AND sys.dbms_logmnr.mine_value(REDO_VALUE, 'CUSTOMER_ID') <>  sys.dbms_logmnr.mine_value(UNDO_VALUE, 'CUSTOMER_ID');

      

      exec sys.dbms_logmnr.end_logmnr;

PROFILE

Undocumented dbms_logmnr.profile( options IN BINARY_INTEGER DEFAULT 0, schema IN VARCHAR2 DEFAULT '', startSCN IN NUMBER DEFAULT 0, endSCN IN NUMBER DEFAULT 0, startTime IN DATE DEFAULT '', endTime IN DATE DEFAULT '', threads IN VARCHAR2 DEFAULT '', logLocation IN VARCHAR2 DEFAULT '', logNameSpecifier IN VARCHAR2 DEFAULT '');

exec dbms_logmnr.profile(endTime => SYSDATE +1);

REMOVE_LOGFILE

Removes a redo log file from an existing list of redo log files for LogMiner to process dbms_logmnr.remove_logfile(LogFileName IN VARCHAR2);

TBD

START_LOGMNR

Begin a log miner session dbms_logmnr.start_logmnr( startscn IN NUMBER DEFAULT 0, endscn IN NUMBER DEFAULT 0, starttime IN DATE DEFAULT '', endtime IN DATE DEFAULT '', dictfilename IN VARCHAR2 DEFAULT '', options IN BINARY_INTEGER DEFAULT 0);

See MINE_VALUE Demo Above