【练习--日志恢复】---正常关库非当前日志组所有成员丢失

1.查询当前的日志组及状态：

10:24:22 SYS@ORA11GR2>select group#,member from v$logfile;

    GROUP# MEMBER
---------- --------------------------------------------------
         3 /u01/app/oracle/oradata/ORA11GR2/redo03.log
         2 /u01/app/oracle/oradata/ORA11GR2/redo02.log
         1 /u01/app/oracle/oradata/ORA11GR2/redo01.log
         3 /u01/app/oracle/disk/redo03b.log
         2 /u01/app/oracle/disk/redo02b.log
         1 /u01/app/oracle/disk/redo01b.log

6 rows selected.

10:24:37 SYS@ORA11GR2>select group#,members,bytes/1024/1024 M,status from v$log;

    GROUP#    MEMBERS          M STATUS
---------- ---------- ---------- ----------------
         1          2         50 INACTIVE
         2          2         50 INACTIVE
         3          2         50 CURRENT

2.关库并删除一个非当前日志组：

10:25:05 SYS@ORA11GR2>shutdown immediate 
Database closed.
Database dismounted.
ORACLE instance shut down.


[oracle@host03 ~]$ rm /u01/app/oracle/disk/redo01b.log
[oracle@host03 ~]$ rm /u01/app/oracle/oradata/ORA11GR2/redo01.log

3.起库时报错：

10:28:00 SYS@ORA11GR2>startup 
ORACLE instance started.

Total System Global Area  830930944 bytes
Fixed Size                  2257800 bytes
Variable Size             536874104 bytes
Database Buffers          289406976 bytes
Redo Buffers                2392064 bytes
Database mounted.
ORA-03113: end-of-file on communication channel
Process ID: 4200
Session ID: 1 Serial number: 5

查看alert日志（提示找不到redo01b.log和redo01.log）：
Errors in file /u01/app/oracle/diag/rdbms/ora11gr2/ORA11GR2/trace/ORA11GR2_ora_4200.trc:
ORA-00313: open failed for members of log group 1 of thread 
ORA-00312: online log 1 thread 1: '/u01/app/oracle/oradata/ORA11GR2/redo01.log'
ORA-00312: online log 1 thread 1: '/u01/app/oracle/disk/redo01b.log'

4.将数据库启动到mount状态：
查看报错日志组是否为当前日志组：

10:36:54 SYS@ORA11GR2>select group#,members,bytes/1024/1024 M,status from v$log;

    GROUP#    MEMBERS          M STATUS
---------- ---------- ---------- ----------------
         1          2         50 INACTIVE[是非当前日志组]
         3          2         50 CURRENT
         2          2         50 INACTIVE

5.clear 日志组：

10:37:05 SYS@ORA11GR2>alter database clear logfile group 1;

Database altered.

6.起库：

10:39:37 SYS@ORA11GR2>alter database open;

Database altered.