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]
[, loadBalancerDefinition])
staticReadwriteSplittingRuleDefinition:
WRITE_STORAGE_UNIT=storageUnitName, READ_STORAGE_UNITS(storageUnitName [, storageUnitName] ... )
dynamicReadwriteSplittingRuleDefinition:
AUTO_AWARE_RESOURCE=autoAwareResourceName [, WRITE_DATA_SOURCE_QUERY_ENABLED=writeDataSourceQueryEnabled]
loadBalancerDefinition:
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 |
storageUnitName |
IDENTIFIER |
已注册的数据源名称 |
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_STORAGE_UNIT=write_ds,
READ_STORAGE_UNITS(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")
);
ALTER READWRITE_SPLITTING RULE ms_group_1 (
WRITE_STORAGE_UNIT=write_ds,
READ_STORAGE_UNITS(read_ds_0,read_ds_1,read_ds_2),
TYPE(NAME="random")
);
DROP READWRITE_SPLITTING RULE ms_group_1;