ALTER RESOURCE GROUP

The ALTER RESOURCE GROUP statement is used to modify a resource group in a database.

Synopsis

AlterResourceGroupStmt ::=
   "ALTER" "RESOURCE" "GROUP" IfExists ResourceGroupName ResourceGroupOptionList

IfExists ::=
    ('IF' 'EXISTS')?

ResourceGroupName ::=
   Identifier

ResourceGroupOptionList ::=
    DirectResourceGroupOption
|   ResourceGroupOptionList DirectResourceGroupOption
|   ResourceGroupOptionList ',' DirectResourceGroupOption

DirectResourceGroupOption ::=
    "RU_PER_SEC" EqOpt stringLit
|   "PRIORITY" EqOpt ResourceGroupPriorityOption
|   "BURSTABLE"
ResourceGroupPriorityOption ::=
    LOW
|   MEDIUM
|   HIGH

TiDB supports the following DirectResourceGroupOption, where Request Unit (RU) is a unified abstraction unit in TiDB for CPU, IO, and other system resources.

Examples

Create a resource group named rg1 and modify its properties.

DROP RESOURCE GROUP IF EXISTS rg1;

Query OK, 0 rows affected (0.22 sec)

CREATE RESOURCE GROUP IF NOT EXISTS rg1
  RU_PER_SEC = 100
  BURSTABLE;

Query OK, 0 rows affected (0.08 sec)

SELECT * FROM information_schema.resource_groups WHERE NAME ='rg1';
+------+------------+----------+-----------+
| NAME | RU_PER_SEC | PRIORITY | BURSTABLE |
+------+------------+----------+-----------+
| rg1  |       100  | MEDIUM   | YES       |
+------+------------+----------+-----------+
1 rows in set (1.30 sec)

ALTER RESOURCE GROUP rg1
  RU_PER_SEC = 200
  PRIORITY = LOW;

Query OK, 0 rows affected (0.08 sec)

SELECT * FROM information_schema.resource_groups WHERE NAME ='rg1';

+------+------------+----------+-----------+
| NAME | RU_PER_SEC | PRIORITY | BURSTABLE |
+------+------------+----------+-----------+
| rg1  |       200  | LOW      | NO        |
+------+------------+----------+-----------+
1 rows in set (1.30 sec)

MySQL compatibility

MySQL also supports ALTER RESOURCE GROUP. However, the acceptable parameters are different from that of TiDB so that they are not compatible.

See also

• DROP RESOURCE GROUP
• CREATE RESOURCE GROUP
• Request Unit (RU)