DROP RESOURCE UNIT

Purpose

You can use this statement to drop a resource unit.

Syntax

DROP RESOURCE UNIT unit_name;

Parameters

Examples

• If a resource unit is not allocated to a resource pool, you can directly drop it.

  obclient> DROP RESOURCE UNIT unit1;
  Query OK, 0 rows affected
  

• If a resource unit is allocated to a resource pool, you cannot directly drop it. You must first remove the resource unit from the resource pool.

  For example, in the following example, resource unit unit1 is allocated to resource pool pool1.

  obclient> CREATE RESOURCE POOL pool1 UNIT='unit1', UNIT_NUM=1, ZONE_LIST=('zone2');
  

  If you directly drop resource unit unit1, an error is returned.

  obclient> DROP RESOURCE UNIT unit1;
  ERROR 4634 (HY000): resource unit 'UNIT1' is referenced by some resource pool
  

  If you still want to remove unit1 from pool1, you can first create a new resource unit named unit2 and allocate unit2 to pool1, and then drop unit1. Here is an example.

  1. Create a new resource unit named unit2.

     obclient> CREATE RESOURCE UNIT unit2 MAX_CPU 4, MEMORY_SIZE '5G', MAX_IOPS 1280,LOG_DISK_SIZE '10G', MIN_CPU=4, MIN_IOPS=1024;
     

  2. Remove unit1 from pool1.

     obclient> ALTER RESOURCE POOL pool1 UNIT='';
     

     Notice

     The ALTER RESOURCE POOL statement can add or remove only one resource unit to or from a resource pool at a time. Therefore, you must remove unit1 from the resource pool and then add unit2 to it.

  3. Allocate unit2 to pool1.

     obclient> ALTER RESOURCE POOL pool1 UNIT='unit2';
     

  4. Drop unit1. The drop operation is successful.

     obclient> DROP RESOURCE UNIT unit1;
     Query OK, 0 rows affected
     

• If a resource unit is allocated to a resource pool, you must drop the resource pool and the resource unit.

  For example, in the following example, resource unit unit1 is allocated to resource pool pool1.

  obclient> CREATE RESOURCE POOL pool1 UNIT='unit1', UNIT_NUM=1, ZONE_LIST=('zone2');
  

  If you directly drop resource unit unit1, an error is returned.

  obclient> DROP RESOURCE UNIT unit1;
  ERROR 4634 (HY000): resource unit 'UNIT1' is referenced by some resource pool
  

  Drop resource pool pool1 and then drop resource unit unit1. The drop operations are successful.

  obclient> DROP RESOURCE POOL pool1;
  Query OK, 0 rows affected
  

  obclient> DROP RESOURCE UNIT unit1;
  Query OK, 0 rows affected
  

References

Delete a resource specification