。
CREATE READWRITE_SPLITTING RULE
语法用于创建读写分离规则。
CreateReadwriteSplittingRule ::=
'CREATE' 'READWRITE_SPLITTING' 'RULE' ifNotExists? readwriteSplittingDefinition (',' readwriteSplittingDefinition)*
ifNotExists ::=
'IF' 'NOT' 'EXISTS'
readwriteSplittingDefinition ::=
ruleName '(' dataSourceDefinition (',' transactionalReadQueryStrategyDefinition)? (',' loadBalancerDefinition)? ')'
dataSourceDefinition ::=
'WRITE_STORAGE_UNIT' '=' writeStorageUnitName ',' 'READ_STORAGE_UNITS' '(' storageUnitName (',' storageUnitName)* ')'
transactionalReadQueryStrategyDefinition ::=
'TRANSACTIONAL_READ_QUERY_STRATEGY' '=' transactionalReadQueryStrategyType
loadBalancerDefinition ::=
'TYPE' '(' 'NAME' '=' algorithmType (',' propertiesDefinition)? ')'
ruleName ::=
identifier
writeStorageUnitName ::=
identifier
storageUnitName ::=
identifier
transactionalReadQueryStrategyType ::=
string
algorithmType ::=
string
propertiesDefinition ::=
'PROPERTIES' '(' key '=' value (',' key '=' value)* ')'
key ::=
string
value ::=
literal
transactionalReadQueryStrategyType
指定事务内读请求路由策略,请参考YAML 配置;algorithmType
指定负载均衡算法类型,请参考负载均衡算法;ruleName
将无法被创建;ifNotExists
子句用于避免出现 Duplicate readwrite_splitting rule
错误。CREATE READWRITE_SPLITTING RULE ms_group_0 (
WRITE_STORAGE_UNIT=write_ds,
READ_STORAGE_UNITS(read_ds_0,read_ds_1),
TYPE(NAME="random")
);
ifNotExists
子句创建读写分离规则CREATE READWRITE_SPLITTING RULE IF NOT EXISTS ms_group_0 (
WRITE_STORAGE_UNIT=write_ds,
READ_STORAGE_UNITS(read_ds_0,read_ds_1),
TYPE(NAME="random")
);
CREATE
、READWRITE_SPLITTING
、RULE
、WRITE_STORAGE_UNIT
、READ_STORAGE_UNITS
、TYPE
、NAME
、PROPERTIES
、TRUE
、FALSE