聯機日志損壞時的恢復（正常關閉數據庫）

發布時間: 2012/9/5 17:39:58

1.創建一個表T2插入兩行數據,第一行數據寫如果歸檔日志,第二行數據在聯機日志中
SQL> create table t2(
a1 number(10),
a2 char(10)) tablespace users; -

SQL> insert into t2 values (11,'aa');
SQL> commit;
SQL> alter system switch logfile;
SQL> insert into t2 values(22,'bb');
SQL> commit;

2.查詢日志文件
SQL> select member from v$logfile;

MEMBER
--------------------------------------------------------------------------------
/database/ykg/ykg1a.log
/database/ykg/ykg2a.log

3.正常關閉數據庫
SQL> shutdown immediate
Database closed.
Database dismounted.
Oracle instance shut down.

4.模擬聯機日志文件損壞
SQL> host rm -rf /database/ykg/ykg*.log

5.正常啟動數據庫報錯
SQL> startup
Oracle instance started.

Total System Global Area 293601280 bytes
Fixed Size                  2020392 bytes
Variable Size              92277720 bytes
Database Buffers          197132288 bytes
Redo Buffers                2170880 bytes
Database mounted.
ORA-00313: open failed for members of log group 1 of thread 1
ORA-00312: online log 1 thread 1: '/database/ykg/ykg1a.log'

6.查看當前聯機日志的SEQUENCE號
SQL> archive log list;
Database log mode              Archive Mode
Automatic archival             Enabled
Archive destination            USE_DB_RECOVERY_FILE_DEST
Oldest online log sequence     191
Next log sequence to archive   192
Current log sequence           192

7.假裝執行不完全恢復來恢復日志組
RMAN> run {
2> recover database until sequence 193 thread 1;
3> alter database open resetlogs;}

8.驗證日志成員已恢復,數據沒有丟失
SQL> select member from v$logfile;
MEMBER
--------------------------------------------------------------------------------
/database/ykg/ykg1a.log
/database/ykg/ykg2a.log