怎么使用log miner分析oracle日志
当我们不小心误操作致使数据库数据丢失、改变时, 需要对数据库对象做基于时间点的恢复,找到我们需要的数据,这个时间点不能认为精确确定,我们可以通过对oracle日志进行分析,而获得无操作的精确时间点。
oracle db提供了一个分析日志包logmnr
logminer 工具的使用
-------对redo log 进行挖掘,找出在某个时间点所作的DDL 或DML 操作(包括:时间点、datablock scn 、sql语句)
实验测试
SQL> select name from v$archived_log; NAME -------------------------------------------------- /oracle/arch1/1_2_883536782.dbf SQL> SQL> SQL> delete from scott.t1; 576 rows deleted. SQL> alter system archive log current; System altered. SQL> create table scott.t6 as select * from scott.emp; Table created. SQL> alter system archive log current; System altered. SQL> select name from v$archived_log; NAME -------------------------------------------------- /oracle/arch1/1_2_883536782.dbf /oracle/arch1/1_3_883536782.dbf /oracle/arch1/1_4_883536782.dbf
--启动log miner添加要分析的日志
SQL> execute dbms_logmnr.add_logfile(logfilename=>'/oracle/arch1/1_2_883536782.dbf',options=>dbms_logmnr.new); PL/SQL procedure successfully completed.
--添加需要分析的日志
SQL> execute dbms_logmnr.add_logfile(logfilename=>'/oracle/arch1/1_3_883536782.dbf',options=>dbms_logmnr.addfile); PL/SQL procedure successfully completed. SQL> execute dbms_logmnr.add_logfile(logfilename=>'/oracle/arch1/1_4_883536782.dbf',options=>dbms_logmnr.addfile) PL/SQL procedure successfully completed.
--执行log miner
SQL> execute dbms_logmnr.start_logmnr(options=>dbms_logmnr.dict_from_online_catalog); PL/SQL procedure successfully completed.
--查询分析结果
SQL> alter session set nls_date_format='yyyy-mm-dd hh24:mi:ss'; Session altered. SQL> select username,scn,timestamp,sql_redo from v$logmnr_contents where seg_name='T1'; USERNAME SCN TIMESTAMP ------------------------------ ---------- ------------------- SQL_REDO -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- delete from "SCOTT"."T1" where "EMPNO" = '7782' and "ENAME" = 'CLARK' and "JOB" = 'MANAGER' and "MGR" = '7839' and "HIREDATE" = TO_DATE('1981-06-09 00:00:00', 'yyyy-mm-dd hh24:mi:ss') and "SAL" = '245 0' and "COMM" IS NULL and "DEPTNO" = '10' and ROWID = 'AAAVbSAAFAAAACXABi'; SYS 1494545 2015-06-28 04:24:44 delete from "SCOTT"."T1" where "EMPNO" = '7839' and "ENAME" = 'KING' and "JOB" = 'PRESIDENT' and "MGR" IS NULL and "HIREDATE" = TO_DATE('1981-11-17 00:00:00', 'yyyy-mm-dd hh24:mi:ss') and "SAL" = '500 0' and "COMM" IS NULL and "DEPTNO" = '10' and ROWID = 'AAAVbSAAFAAAACXABj'; SYS 1494545 2015-06-28 04:24:44 delete from "SCOTT"."T1" where "EMPNO" = '7844' and "ENAME" = 'TURNER' and "JOB" = 'SALESMAN' and "MGR" = '7698' and "HIREDATE" = TO_DATE('1981-09-08 00:00:00', 'yyyy-mm-dd hh24:mi:ss') and "SAL" = '1 。。。。。
--结束log miner 分析
SQL> execute dbms_logmnr.end_logmnr; PL/SQL procedure successfully completed.
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程序猿都知道mysql等其他的数据库都有随着记录的插入而表ID会自动增长的功能,反而oracle却没有这一功能,下面通过两种方式来解决字段增长的功能,具体内容情况下文。因为两种方式都需要通过创建序 ...