Recover a tenant

To prevent irreversible data loss caused by malicious or accidental operations, OceanBase Database provides the recycle bin feature, which supports the quick recovery of tenant-level data. This topic describes how to recover a tenant from the recycle bin.

OceanBase Database supports recovering a tenant from the recycle bin using the FLASHBACK TENANT statement.

Limitations

Since only the sys tenant can drop tenants, tenants in MySQL mode and Oracle mode can only be moved to the recycle bin of the sys tenant after being dropped. Only the sys tenant can perform tenant recovery operations.

Procedure

1. Log in to the sys tenant of the cluster using the root user.

   obclient -h172.30.xx.xx -P2883 -uroot@sys#cluster -p**** -A
   

2. Access the database named oceanbase.

   obclient [(none)]> USE oceanbase;
   

3. Execute the SHOW RECYCLEBIN statement to view the objects in the recycle bin of the current sys tenant.

   obclient [oceanbase]> SHOW RECYCLEBIN;
   +-------------------------------------+---------------+--------+----------------------------+
   | OBJECT_NAME                         | ORIGINAL_NAME | TYPE  | CREATETIME                   |
   +-------------------------------------+---------------+--------+----------------------------+
   | __recycle_$_100017_1673367572701376 | mq_t1         | TENANT | 2023-01-11 00:23:36.317242 |
   +-------------------------------------+---------------+--------+----------------------------+
   1 row in set
   

   For more information about recycle bin related parameters, see Recycle bin.

4. Execute the FLASHBACK TENANT statement to recover a tenant from the recycle bin. For example, to recover the mq_t1 tenant:

   obclient [oceanbase]> FLASHBACK TENANT mq_t1 TO BEFORE DROP;
   Query OK, 0 rows affected
   

   For more information about the FLASHBACK TENANT statement, see FLASHBACK.

5. Query the DBA_OB_TENANTS view and recycle bin to check the execution result.

   obclient [oceanbase]> SHOW RECYCLEBIN;
   Empty set
   
   obclient [oceanbase]> SELECT * FROM DBA_OB_TENANTS WHERE TENANT_NAME = 'mq_t1';
   +-----------+-------------+-------------+----------------------------+----------------------------+--------------+------------------------------+-------------------+--------------------+--------+---------------+--------+-------------+-------------------+------------------+---------------------+---------------------+---------------------+---------------------+--------------+----------------------------+
   | TENANT_ID | TENANT_NAME | TENANT_TYPE | CREATE_TIME                | MODIFY_TIME                | PRIMARY_ZONE | LOCALITY                     | PREVIOUS_LOCALITY | COMPATIBILITY_MODE | STATUS | IN_RECYCLEBIN | LOCKED | TENANT_ROLE | SWITCHOVER_STATUS | SWITCHOVER_EPOCH | SYNC_SCN            | REPLAYABLE_SCN      | READABLE_SCN        | RECOVERY_UNTIL_SCN  | LOG_MODE     | ARBITRATION_SERVICE_STATUS |
   +-----------+-------------+-------------+----------------------------+----------------------------+--------------+------------------------------+-------------------+--------------------+--------+---------------+--------+-------------+-------------------+------------------+---------------------+---------------------+---------------------+---------------------+--------------+----------------------------+
   |      1036 | mq_t1       | USER        | 2023-01-11 00:23:36.317242 | 2023-05-18 15:49:12.857944 | zone1;zone2  | FULL{1}@zone1, FULL{1}@zone2 | NULL              | MYSQL              | NORMAL | NO            | NO     | PRIMARY     | NORMAL            |                0 | 1684396167132057328 | 1684396167132057328 | 1684396167051160964 | 4611686018427387903 | NOARCHIVELOG | DISABLED                   |
   +-----------+-------------+-------------+----------------------------+----------------------------+--------------+------------------------------+-------------------+--------------------+--------+---------------+--------+-------------+-------------------+------------------+---------------------+---------------------+---------------------+---------------------+--------------+----------------------------+
   1 row in set
   

References

For more information about dropping tenants and the recycle bin, see the following topics:

• Drop a tenant

• Recycle bin

• Restore objects from the recycle bin