FLASHBACK实施笔记

 一、启用FLASHBACK

1、更改参数（在6节点执行如下脚本）

shutdown immediate;

startup mount;

alter system set db_recovery_file_dest_size=4G scope=both;

alter system set db_recovery_file_dest='/home/oracle/archlog' scope=both;

alter database flashback on;

alter database open;

2、确认

是否启用闪回

select FLASHBACK_ON from v$database;

闪回恢复区的内容

select file_type from v$flash_recovery_area_usage;

其他参数

show parameter DB_FLASHBACK_RETENTION_TARGET；

show parameter DB_RECOVERY_FILE_DEST_SIZE；

show parameter DB_RECOVERY_FILE_DEST；

3、记录脚本执行前SYSDATE

select to_char(sysdate, 'yyyy-mm-dd hh24:mi:ss') from dual;

4、表启用ROW MOVEMENT

ALTER TABLE INDUSTRY testflashback ROW MOVEMENT;

5、测试闪回（testflashback表）

select Count(*) from testflashback t;

COUNT(*)

5

delete from testflashback;

commit;

flashback table testflashback to timestamp to_date('2012-11-30 22:00:00','yyyy-mm-dd hh24:mi:ss');

select Count(*) from testflashback t;

COUNT(*)

二、关闭FLASHBACK

shutdown immediate;

startup mount;

alter database flashback off;

alter database open;

alter system set db_recovery_file_dest='' scope=both;