Description
You can execute the FLASHBACK TABLE statement to restore a deleted table from the recycle bin.
Prerequisites
The recycle bin is enabled. You can execute the following statement to check whether the recycle bin is enabled:
show variables like 'recyclebin';
OceanBase(admin@test)> show variables like 'recyclebin';
+---------------+-------+
| Variable_name | Value |
+---------------+-------+
| recyclebin | ON |
+---------------+-------+
1 row in set (0.00 sec)
If the recycle bin is disabled, you can execute the following statement to enable it:
set recyclebin = on;
Tables in the recycle bin are not deleted from the database and still consume resources. To delete them from the database, execute the following statement:
purge recyclebin;
Syntax
FLASHBACK TABLE object_name TO BEFORE DROP [RENAME to db_name.table_name];
Parameters
| Parameter | Description |
|---|---|
| object_name | The name of the object or table that you want to restore. Before you execute FLASHBACK TABLE to restore a table, log on to the database where the table is stored. When you restore a table, the index of the table is also restored. |
| RENAME to | Rename the table and database to which the table belongs. |
Examples
- Restore deleted table t from the recycle bin.
OceanBase(admin@test)> create table t(id int primary key, k int);
Query OK, 0 rows affected (0.04 sec)
OceanBase(admin@test)> insert into t values(1,1);
Query OK, 1 row affected (0.00 sec)
OceanBase(admin@test)> select * from t;
+----+------+
| id | k |
+----+------+
| 1 | 1 |
+----+------+
1 row in set (0.00 sec)
OceanBase(admin@test)> drop table t;
Query OK, 0 rows affected (0.01 sec)
OceanBase(admin@test)> select * from t;
ERROR 1146 (42S02): Table 'test.t' does not exist
OceanBase(admin@test)> show recyclebin;
+--------------------------------+---------------+-------+----------------------------+
| OBJECT_NAME | ORIGINAL_NAME | TYPE | CREATETIME |
+--------------------------------+---------------+-------+----------------------------+
| __recycle_$_1_1597028971700936 | t | TABLE | 2020-08-10 11:09:31.701033 |
+--------------------------------+---------------+-------+----------------------------+
1 row in set (0.00 sec)
OceanBase(admin@test)> flashback table t to before drop;
Query OK, 0 rows affected (0.01 sec)
OceanBase(admin@test)> select * from t;
+----+------+
| id | k |
+----+------+
| 1 | 1 |
+----+------+
1 row in set (0.00 sec)
