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读写分离

语法说明

CREATE READWRITE_SPLITTING RULE readwriteSplittingRuleDefinition [, readwriteSplittingRuleDefinition] ...

ALTER READWRITE_SPLITTING RULE readwriteSplittingRuleDefinition [, readwriteSplittingRuleDefinition] ...

DROP READWRITE_SPLITTING RULE ruleName [, ruleName] ...

readwriteSplittingRuleDefinition:
    ruleName ([staticReadwriteSplittingRuleDefinition | dynamicReadwriteSplittingRuleDefinition] 
              [, loadBanlancerDefinition])

staticReadwriteSplittingRuleDefinition:
    WRITE_RESOURCE=writeResourceName, READ_RESOURCES(readResourceName [, readResourceName] ... )

dynamicReadwriteSplittingRuleDefinition:
    AUTO_AWARE_RESOURCE=autoAwareResourceName [, WRITE_DATA_SOURCE_QUERY_ENABLED=writeDataSourceQueryEnabled]

loadBanlancerDefinition:
    TYPE(NAME=loadBalancerType [, PROPERTIES([algorithmProperties] )] )

algorithmProperties:
    algorithmProperty [, algorithmProperty] ...

algorithmProperty:
    key=value

writeDataSourceQueryEnabled:
    TRUE | FALSE

参数解释

名称 数据类型 说明
ruleName IDENTIFIER 规则名称
writeResourceName IDENTIFIER 写库数据源名称
readResourceName IDENTIFIER 读库数据源名称
autoAwareResourceName IDENTIFIER 数据库发现的逻辑数据源名称
writeDataSourceQueryEnabled BOOLEAN 读库全部下线，主库是否承担读流量
loadBalancerType STRING 负载均衡算法类型

注意事项

  • 支持创建静态读写分离规则和动态读写分离规则；
  • 动态读写分离规则依赖于数据库发现规则；
  • loadBalancerType 指定负载均衡算法类型，请参考 负载均衡算法；
  • 重复的 ruleName 将无法被创建。

示例

// Static
CREATE READWRITE_SPLITTING RULE ms_group_0 (
WRITE_RESOURCE=write_ds,
READ_RESOURCES(read_ds_0,read_ds_1),
TYPE(NAME="random")
);

// Dynamic
CREATE READWRITE_SPLITTING RULE ms_group_1 (
AUTO_AWARE_RESOURCE=group_0,
WRITE_DATA_SOURCE_QUERY_ENABLED=false,
TYPE(NAME="random",PROPERTIES("read_weight"="2:1"))
);

ALTER READWRITE_SPLITTING RULE ms_group_1 (
WRITE_RESOURCE=write_ds,
READ_RESOURCES(read_ds_0,read_ds_1,read_ds_2),
TYPE(NAME="random",PROPERTIES("read_weight"="2:0"))
);

DROP READWRITE_SPLITTING RULE ms_group_1;