Drop a resource pool

This topic describes how to drop a resource pool.

Prerequisites

Before you drop a resource pool, make sure that the resource pool is not being used by any tenant. To drop a resource pool being used by a tenant, release the resource pool first and then drop it.

• If a tenant has multiple resource pools, you can modify the resource pool configuration of the tenant to drop a resource pool from the tenant. For more information, see Modify attributes of a tenant.

• If a tenant has only one resource pool, you cannot directly drop it.

  • Create a resource pool and allocate it to this tenant. Then, modify the resource pool configuration of the tenant to release the resource pool to be dropped. For more information about how to create a resource pool, see the Create a resource pool section in the Create a tenant topic.
  • If the tenant is no longer needed, you can drop the tenant first and then drop the resource pool. For more information, see Drop a tenant.

Procedure

1. Log on to the sys tenant of the cluster as the root user.

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

2. Execute the following statement to go to the database named oceanbase:

   obclient [(none)]> USE oceanbase;
   

3. Query the DBA_OB_RESOURCE_POOLS view for the configuration information about resource pools. If the value of TENANT_ID of a resource pool is NULL, the resource pool is not allocated to any tenant and can be dropped.

   To query the configuration information about the resource pool named mq_pool_02, execute the following statement:

   obclient [oceanbase]> SELECT TENANT_ID,NAME FROM DBA_OB_RESOURCE_POOLS WHERE NAME = 'mq_pool_02';
   +-----------+------------+
   | tenant_id | name       |
   +-----------+------------+
   |      NULL | mq_pool_02 |
   +-----------+------------+
   1 row in set
   

   For more information about the DBA_OB_RESOURCE_POOLSview, see oceanbase.DBA_OB_RESOURCE_POOLS.

4. Execute the DROP RESOURCE POOL statement to drop a resource pool.

   To drop the resource pool named mq_pool_02, execute the following statement:

   obclient [oceanbase]> DROP RESOURCE POOL mq_pool_02;
   Query OK, 0 rows affected
   

   For more information about the DROP RESOURCE POOL statement, see DROP RESOURCE POOL.

5. Query the DBA_OB_RESOURCE_POOLS view to verify whether the resource pool is successfully dropped.

   obclient [oceanbase]> SELECT * FROM DBA_OB_RESOURCE_POOLS WHERE NAME = 'mq_pool_02';
   Empty set
   

More information

• Create a tenant

• Modify attributes of a tenant