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HomeDatabaseMysql TutorialOracle 11g之LogMiner常用场景

1 LogMiner 常用场景 1.1 用 LogMiner 跟踪特定用户所做的更改 本节例子,查出用户joedevo在特定时间范围内对数据库所做的所有操作,步骤如下: 1.创建LogMiner字典 使用LogMiner分析joedevo相关的数据,必须在joedevo对它的所有表做任何的更改操作前创建Lo

LogMiner常用场景


1.1 LogMiner跟踪特定用户所做的更改


本节例子,查出用户joedevo在特定时间范围内对数据库所做的所有操作,步骤如下:

1.创建LogMiner字典

   使用LogMiner分析joedevo相关的数据,必须在joedevo对它的所有表做任何的更改操作前创建LogMiner字典或者直接使用在线字典,本例使用已提取到重做日志文件中的LogMiner字典。

2.添加重做日志文件

在joedevo对数据库做了一些更改操作之后,可以指定对应的重做日志文件来分析:

SQL> EXECUTE DBMS_LOGMNR.ADD_LOGFILE( -

   LOGFILENAME => 'log1orc1.ora', -

   OPTIONS => DBMS_LOGMNR.NEW);

根据需要添加其他的重做日志文件:

SQL> EXECUTE DBMS_LOGMNR.ADD_LOGFILE( -

   LOGFILENAME => 'log2orc1.ora', -

   OPTIONS => DBMS_LOGMNR.ADDFILE);

3.开启LogMiner并限制查询范围

SQL> EXECUTE DBMS_LOGMNR.START_LOGMNR( -

   DICTFILENAME => 'orcldict.ora', -

   STARTTIME => TO_DATE('01-Jan-1998 08:30:00','DD-MON-YYYY HH:MI:SS'), - ENDTIME => TO_DATE('01-Jan-1998 08:45:00', 'DD-MON-YYYY HH:MI:SS'));

4.查询V$LOGMNR_CONTENTS

SQL> SELECT SQL_REDO, SQL_UNDO FROM V$LOGMNR_CONTENTS

   WHERE USERNAME = 'joedevo' AND SEG_NAME = 'salary';

5.停止LogMiner

SQL> EXECUTE DBMS_LOGMNR.END_LOGMNR();


1.2 LogMiner做表的访问统计


   本节案例中,假设你管理者一个直营数据库,想确定1月份2周内客户带来的生产效益,假定你已经创建了LogMiner字典并添加了相关的重做日志文件,接下来的步骤如下:

1.开始LogMiner并限制查询范围

SQL> EXECUTE DBMS_LOGMNR.START_LOGMNR( -

   STARTTIME => TO_DATE('07-Jan-2003 08:30:00','DD-MON-YYYY HH:MI:SS'), -

   ENDTIME => TO_DATE('21-Jan-2003 08:45:00','DD-MON-YYYY HH:MI:SS'), -

   DICTFILENAME => '/usr/local/dict.ora');

2.查询V$LOGMNR_CONTENTS

查询V$LOGMNR_CONTENTS确定指定时间范围内哪些表发生了变化:

SQL> SELECT SEG_OWNER, SEG_NAME, COUNT(*) AS Hits FROM

   V$LOGMNR_CONTENTS WHERE SEG_NAME NOT LIKE '%$' GROUP BY

   SEG_OWNER, SEG_NAME ORDER BY Hits DESC;

3.停止LogMiner

SQL> EXECUTE DBMS_LOGMNR.END_LOGMNR();



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