描述

用于从回收站中恢复被删除的表。

前置条件

回收站需要处于开启状态，可以通过​SHOW VARIABLES LIKE 'recyclebin';​来查看回收站是否开启。

obclient>SHOW VARIABLES LIKE 'recyclebin';+---------------+-------+| Variable_name | Value |+---------------+-------+| recyclebin    | ON    |+---------------+-------+1 row in set (0.00 sec)

如果回收站处于关闭状态，可以通过​SET RECYCLEBIN = ON;​来开启。回收站中的表没有被实际删除，仍然会占用资源，如果需要彻底删除，可以执行​PURGE RECYCLEBIN;​

格式

 FLASHBACK TABLE object_name TO BEFORE DROP [RENAME to db_name.table_name];

参数解释

参数

描述

object_name

指定要恢复的对象名称或表名，只有在表所在的数据库中才能执行。恢复表时，也会同步恢复和表相关的索引。

RENAME to

修改表名和表所属的库。

示例

从回收站中恢复被删除的表 t。

obclient>CREATE TABLE t(id INT PRIMARY KEY, k INT);Query OK, 0 rows affected (0.04 sec)obclient>INSERT INTO t VALUES(1,1);Query OK, 1 row affected (0.00 sec)obclient>SELECT * FROM t;+----+------+| id | k    |+----+------+|  1 |    1 |+----+------+1 row in set (0.00 sec)obclient>DROP TABLE t;Query OK, 0 rows affected (0.01 sec)obclient>SELECT * FROM t;ORA-00942: table or view 'SYS.T' does not existobclient>SHOW RECYCLEBIN;+--------------------------------+---------------+-------+----------------------------+| OBJECT_NAME                    | ORIGINAL_NAME | TYPE  | CREATETIME                 |+--------------------------------+---------------+-------+----------------------------+| RECYCLE_$_2_1616038871797032 | T             | TABLE | 18-MAR-21 11.41.11.797691 AM|+--------------------------------+---------------+-------+----------------------------+1 row in set (0.00 sec)obclient>FLASHBACK TABLE t TO BEFORE DROP;Query OK, 0 rows affected (0.01 sec)obclient>SELECT * FROM t;+----+------+| id | k    |+----+------+|  1 |    1 |+----+------+1 row in set (0.00 sec)