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CREATE DB_DISCOVERY RULE

描述

CREATE DB_DISCOVERY RULE 语法用于创建数据库发现规则

语法定义

CreateDatabaseDiscoveryRule ::=
  'CREATE' 'DB_DISCOVERY' 'RULE' ifNotExists? databaseDiscoveryDefinition (',' databaseDiscoveryDefinition)*

ifNotExists ::=
  'IF' 'NOT' 'EXISTS'

databaseDiscoveryDefinition ::=
  ruleName '(' 'STORAGE_UNITS' '(' storageUnitName (',' storageUnitName)* ')' ',' 'TYPE' '(' 'NAME' '=' typeName (',' propertiesDefinition)? ')' ',' 'HEARTBEAT' '(' propertiesDefinition ')' ')' 

propertiesDefinition ::=
  'PROPERTIES' '(' key '=' value (',' key '=' value)* ')'

ruleName ::=
  identifier

storageUnitName ::=
  identifier

typeName ::=
  identifier

discoveryHeartbeatName ::=
  identifier

key ::=
  string

value ::=
  literal

补充说明

  • discoveryType 指定数据库发现服务类型，ShardingSphere 内置支持 MySQL.MGR；
  • 重复的 ruleName 将无法被创建；
  • ifNotExists 子句用于避免出现 Duplicate db_discovery rule 错误。

示例

  • 创建数据库发现规则
CREATE DB_DISCOVERY RULE db_discovery_group_0 (
    STORAGE_UNITS(ds_0, ds_1, ds_2),
    TYPE(NAME='MySQL.MGR',PROPERTIES('group-name'='92504d5b-6dec')),
    HEARTBEAT(PROPERTIES('keep-alive-cron'='0/5 * * * * ?'))
);
  • 使用 ifNotExists 子句创建数据库发现规则
CREATE DB_DISCOVERY RULE IF NOT EXISTS db_discovery_group_0 (
    STORAGE_UNITS(ds_0, ds_1, ds_2),
    TYPE(NAME='MySQL.MGR',PROPERTIES('group-name'='92504d5b-6dec')),
    HEARTBEAT(PROPERTIES('keep-alive-cron'='0/5 * * * * ?'))
);

保留字

CREATE、DB_DISCOVERY、RULE、STORAGE_UNITS、TYPE、NAME、PROPERTIES、HEARTBEAT

相关链接