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CREATE PLACEMENT POLICY
The usage of CREATE PLACEMENT POLICY in TiDB.

CREATE PLACEMENT POLICY

CREATE PLACEMENT POLICY is used to create a named placement policy that can later be assigned to tables, partitions, or database schemas.

Note:

This feature is not available on TiDB Serverless clusters.

Synopsis

CreatePolicyStmt ::=
    "CREATE" "PLACEMENT" "POLICY" IfNotExists PolicyName PlacementOptionList

PolicyName ::=
    Identifier

PlacementOptionList ::=
    PlacementOption
|   PlacementOptionList PlacementOption
|   PlacementOptionList ',' PlacementOption

PlacementOption ::=
    CommonPlacementOption
|   SugarPlacementOption
|   AdvancedPlacementOption

CommonPlacementOption ::=
    "FOLLOWERS" EqOpt LengthNum

SugarPlacementOption ::=
    "PRIMARY_REGION" EqOpt stringLit
|   "REGIONS" EqOpt stringLit
|   "SCHEDULE" EqOpt stringLit

AdvancedPlacementOption ::=
    "LEARNERS" EqOpt LengthNum
|   "CONSTRAINTS" EqOpt stringLit
|   "LEADER_CONSTRAINTS" EqOpt stringLit
|   "FOLLOWER_CONSTRAINTS" EqOpt stringLit
|   "LEARNER_CONSTRAINTS" EqOpt stringLit
|   "SURVIVAL_PREFERENCES" EqOpt stringLit

Examples

Note:

To know which regions are available in your cluster, see SHOW PLACEMENT LABELS.

If you do not see any available regions, your TiKV installation might not have labels set correctly.

{{< copyable "sql" >}}

CREATE PLACEMENT POLICY p1 PRIMARY_REGION="us-east-1" REGIONS="us-east-1,us-west-1" FOLLOWERS=4;
CREATE TABLE t1 (a INT) PLACEMENT POLICY=p1;
SHOW CREATE PLACEMENT POLICY p1;
Query OK, 0 rows affected (0.08 sec)

Query OK, 0 rows affected (0.10 sec)

+--------+---------------------------------------------------------------------------------------------------+
| Policy | Create Policy                                                                                     |
+--------+---------------------------------------------------------------------------------------------------+
| p1     | CREATE PLACEMENT POLICY `p1` PRIMARY_REGION="us-east-1" REGIONS="us-east-1,us-west-1" FOLLOWERS=4 |
+--------+---------------------------------------------------------------------------------------------------+
1 row in set (0.00 sec)

MySQL compatibility

This statement is a TiDB extension to MySQL syntax.

See also