ALTER SHARDING TABLE REFERENCE RULE

Description

The ALTER SHARDING TABLE REFERENCE RULE syntax is used to alter sharding table reference rule.

Syntax

Grammar Railroad diagram

  1. AlterShardingTableReferenceRule ::=
  2.   'ALTER' 'SHARDING' 'TABLE' 'REFERENCE' 'RULE'  referenceRelationshipDefinition  (',' referenceRelationshipDefinition)*
  4. referenceRelationshipDefinition ::=
  5.   ruleName '(' tableName (',' tableName)* ')'
  7. ruleName ::=
  8.   identifier
  10. tableName ::=
  11.   identifier

Supplement

  • A sharding table can only be associated with one sharding table reference rule;
  • The referenced sharding tables should be sharded in the same storage units and have the same number of sharding nodes. For example ds_${0..1}.t_order_${0..1} and ds_${0..1}.t_order_item_${0..1};
  • The referenced sharding tables should use consistent sharding algorithms. For example t_order_{order_id % 2} and t_order_item_{order_item_id % 2};

Example

1. Alter a sharding table reference rule

  1. ALTER SHARDING TABLE REFERENCE RULE ref_0 (t_order,t_order_item);

2. Alter multiple sharding table reference rules

  1. ALTER SHARDING TABLE REFERENCE RULE ref_0 (t_order,t_order_item), ref_1 (t_product,t_product_item);

Reserved word

ALTER, SHARDING, TABLE, REFERENCE, RULE