闪回恢复区开启

闪回恢复区开启需要先指定闪回恢复区大小（db_recovery_file_dest_size），再指定闪回恢复区目录（db_recovery_file_dest）。

 

1、设置db_recovery_file_dest_size参数大小

SQL> alter system set db_recovery_file_dest_size=2048m;

 

System altered.

2、设置db_recovery_file_dest值

SQL> alter system set db_recovery_file_dest='/u01/app/oracle/PROD2';

 

System altered.

3、查看修改后参数值

SQL> show parameter recovery

 

NAME TYPE VALUE

------------------------------------ ----------- ------------------------------

db_recovery_file_dest string /u01/app/oracle/PROD2

db_recovery_file_dest_size big integer 2G

4、开启闪回功能

SQL> alter database flashback on;

 

Database altered.

5、查询是否开启成功

SQL> select NAME,LOG_MODE,FORCE_LOGGING,FLASHBACK_ON from v$database;

 

NAME LOG_MODE FOR FLASHBACK_ON

--------- ------------ --- ------------------

PROD2 ARCHIVELOG YES YES