如何启用Oracle10g闪回数据库特性

1.确认当前模式

SYS AS SYSDBA on 29-MAR-05 >select flashback_on from v$database;

FLA
---
NO

2.检查/修改恢复区设置

SYS AS SYSDBA on 29-MAR-05 >show parameter db_recovery_file_dest

NAME                                 TYPE        VALUE
------------------------------------ ----------- ------------------------------
db_recovery_file_dest                string      /data5/flash_recovery_area
db_recovery_file_dest_size           big integer 10G

3.检查/修改闪回时间设置

SYS AS SYSDBA on 29-MAR-05 >show parameter db_flashback_retention_target

NAME                                 TYPE        VALUE
------------------------------------ ----------- ------------------------------
db_flashback_retention_target        integer     60
SYS AS SYSDBA on 29-MAR-05 >alter system set db_flashback_retention_target=1440;

System altered.

4.重新启动数据库到Mount状态
启动flashback database选项。

SYS AS SYSDBA on 29-MAR-05 >shutdown immediate;
Database closed.
Database dismounted.
ORACLE instance shut down.
SYS AS SYSDBA on 29-MAR-05 >startup mount;
ORACLE instance started.

Total System Global Area  314572800 bytes
Fixed Size                  1301704 bytes
Variable Size             261890872 bytes
Database Buffers           50331648 bytes
Redo Buffers                1048576 bytes
Database mounted.
SYS AS SYSDBA on 29-MAR-05 >alter database flashback on;

Database altered.

SYS AS SYSDBA on 29-MAR-05 >alter database open;

Database altered.