在進行不完全恢複案例演練之前,我們要先學會如何使用logminer工具。該工具主要對redo log 進行挖掘,找出在某個時間點所作的DDL 或DML 操作(包括:時間點、datablock scn 、sql語句)
1、對DML 分析
SQL> select * from scott.tb01;
ID
----------
1
2
3
3 rows selected.
SQL> delete from scott.tb01;
3 rows deleted.
SQL> commit;
Commit complete.
SQL> insert into scott.tb01 values(111);
1 row created.
SQL> insert into scott.tb01 values(222);
1 row created.
SQL> insert into scott.tb01 values(333);
1 row created.
SQL> commit;
Commit complete.
SQL> select * from scott.tb01;
ID
----------
111
222
333
3 rows selected.
(1)查看當前日誌組
SQL> select * from v$log;
GROUP# THREAD# SEQUENCE# BYTES MEMBERS ARCHIVED STATUS FIRST_CHANGE# FIRST_TIME
---------- ---------- ---------- ---------- ---------- --------- ---------- ------------- -------------------
1 1 1 104857600 3 YES INACTIVE 846224 2012-03-22 15:46:28
4 1 0 104857600 3 YES UNUSED 0
3 1 3 104857600 3 NO CURRENT 847894 2012-03-22 16:30:10
2 1 2 104857600 3 YES INACTIVE 846225 2012-03-22 15:47:06
SQL> alter system archive log current;——使當前日誌組歸檔
System altered.
SQL> select * from v$log;
GROUP# THREAD# SEQUENCE# BYTES MEMBERS ARCHIVED STATUS FIRST_CHANGE# FIRST_TIME
---------- ---------- ---------- ---------- ---------- --------- ---------- ------------- -------------------
1 1 5 104857600 3 NO CURRENT 849696 2012-03-22 17:36:01
4 1 4 104857600 3 YES ACTIVE 849665 2012-03-22 17:34:34
3 1 3 104857600 3 YES ACTIVE 847894 2012-03-22 16:30:10
2 1 2 104857600 3 YES INACTIVE 846225 2012-03-22 15:47:06
4 rows selected.
*********************************以上接案例1***********************************
2、啟用logmnr
(1)添加database補充日誌
17:13:47 SQL> alter database add supplemental log data; ——不添加後面會出錯