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CREATE SHARDING ALGORITHM

Description

The CREATE SHARDING ALGORITHM syntax is used to create a sharding algorithm for the currently selected database.

Syntax

CreateShardingAlgorithm ::=
  'CREATE' 'SHARDING' 'ALGORITHM' shardingAlgorithmName '(' algorithmDefinition ')'

algorithmDefinition ::=
  'TYPE' '(' 'NAME' '=' algorithmType ( ',' 'PROPERTIES'  '(' propertyDefinition  ')' )?')'  

propertyDefinition ::=
  ( key  '=' value ) ( ',' key  '=' value )*

shardingAlgorithmName ::=
  identifier
  
algorithmType ::=
  string

Supplement

  • algorithmType is the sharding algorithm type. For detailed sharding algorithm type information, please refer to Sharding Algorithm.

Example

1.Create sharding algorithms

-- create a sharding algorithm of type INLINE
CREATE SHARDING ALGORITHM inline_algorithm (
    TYPE(NAME="inline", PROPERTIES("algorithm-expression"="t_order_${user_id % 2}"))
);

-- create a sharding algorithm of type AUTO_INTERVAL
CREATE SHARDING ALGORITHM interval_algorithm (
    TYPE(NAME="auto_interval", PROPERTIES("datetime-lower"="2022-01-01 00:00:00", "datetime-upper"="2022-01-03 00:00:00", "sharding-seconds"="86400"))
);

Reserved word

CREATE, SHARDING, ALGORITHM, TYPE, NAME, PROPERTIES