Oracle日志挖掘(LogMnr) ①在参数文件中设置utl_file_dir路径 ②重启 ③创建directory file,使用execute dbms_
Oracle日志挖掘(LogMnr)
①在参数文件中设置utl_file_dir路径
②重启
③创建directory file,使用execute dbms_logmnr_d.build()
④添加日志文件,使用dbms_logmnr.add_logfile
或删除日志文件,使用dbms_logmnr.removefile
⑤启动logmnr,使用dbms_logmnr.start_logmnr
⑥查询,使用V$logmnr_contents(sqlredo/sqlundo)
设置utl_file_dir目录。
alter system set utl_file_dir='D:\app\Leo\utl_file_dir' scope=spfile;
建立日志挖掘的数据字典。
execute dbms_logmnr_d.build('shwdict.ora','D:\app\Leo\utl_file_dir'); //第二个参数要与参数utl_file_dir的设置完全匹配。
无此包,则需执行@d:\oracle\ora8\rdbms\admin\dbmslmd.sql;
创建分析的文件列表(可以是在线或归档日志)
execute dbms_logmnr.add_logfile('D:\app\Leo\archivelog1\ARC00011_0720116156.001',dbms_logmnr.new);
execute dbms_logmnr.add_logfile('D:\app\Leo\archivelog1\ARC00012_0720116156.001',dbms_logmnr.addfile);
execute dbms_logmnr.add_logfile('D:\app\Leo\archivelog1\ARC00013_0720116156.001',dbms_logmnr.addfile);
option:new-创建一个新的日志列表。addfile-向列表中添加日志文件。
remove_logfile-删除。
在视图v$logmnr_logs中可以看到添加的日志列表。
select log_id,filename from v$logmnr_logs;
开始分析
execute dbms_logmnr.start_logmnr(dictfilename=>'D:\app\Leo\utl_file_dir\shwdict.ora');
execute dbms_logmnr.start_logmnr(dictfilename=>'d:\oracle\shwdict.ora',startscn=>xxxxxx,endscn=>xxxxx,starttime=>to_date('20030501 12:15:00','yyyymmdd hh24:mi:ss'), endtime=>to_date('20030501 15:40:30','yyyymmdd hh24:mi:ss'));
没有建立数据字典,使用dbms_logmnr.dict_from_online_catalog选项参数,则logminer期望在所指定的dbms_logmnr.add_logfile或重做日志中找到数据字典。
exec sys.dbms_logmnr.start_logmnr(options=>sys.dbms_logmnr.dict_from_online_catalog);
查询分析内容
select to_char(timestamp,'yyyy-mm-dd hh24:mi:ss') time,sql_redo from v$logmnr_contents where seg_owner='SCOTT';
结束分析
execute dbms_logmnr.end_logmnr;
部分日志归档不出的解决
①将数据库至于force logging模式
alter database force logging;
select force_logging from v$database;
②查看表是否处于归档模式
select table_name,logging from user_tables;
③查看数据库是否处于启用了补充日志(启动了,则每条update写redo时会附加列值唯一信息)
SQL> select supplemental_log_data_pk,supplemental_log_data_ui from v$database;
SUPPLEMENTAL_LOG_DATA_PK SUPPLEMENTAL_LOG_DATA_UI
------------------------ ------------------------
NO NO
SQL> alter database add supplemental log data (primary key,unique index) columns;
Database altered
SQL> select supplemental_log_data_pk,supplemental_log_data_ui from v$database;
SUPPLEMENTAL_LOG_DATA_PK SUPPLEMENTAL_LOG_DATA_UI
------------------------ ------------------------
YES YES

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