mycat 单库分表

上次把mycat的读写分离搞定了，这次试下单库分表，顾名思义就是在一个库里把一个表拆分为多个

需要配置的配置文件为

schema.xml

配置内容如下

<!DOCTYPE mycat:schema SYSTEM "schema.dtd">
<mycat:schema xmlns:mycat="http://io.mycat/">
        <schema name="app_house" checkSQLschema="false" sqlMaxLimit="100">
          <table name="t_order" primaryKey="id" autoIncrement="true" subTables="t_order$1-3" dataNode="dn1" rule="mod-long" /> 
        </schema>
        <dataNode name="dn1" dataHost="mycluster" database="testdb2" />
        <dataHost name="mycluster" maxCon="1000" minCon="10" balance="1"  writeType="0" dbType="mysql" dbDriver="native" switchType="1"  slaveThreshold="100">
          <heartbeat>select user()</heartbeat>
          <!-- can have multi write hosts -->
          <writeHost host="86_M" url="172.17.3.86:3306" user="root" password="123456">
            <!-- can have multi read hosts -->
          <readHost host="177_S" url="172.17.3.177:3306" user="root" password="123456" />
          </writeHost>
          <!-- <writeHost host="hostM2" url="localhost:3316" user="root" password="123456"/> -->
        </dataHost>
</mycat:schema>

上面主要的配置在于table 标签设置

我们测试的单库分表要分的表为t_order，分表规则为mod-long，分布在一个数据库内的三个表上 t_order$1-3 等价于 t_order1，t_order2，t_order3

需要注意的rule.xml里的mod-long规则设置

<function name="mod-long" class="io.mycat.route.function.PartitionByMod">
                <!-- how many data nodes -->
                <property name="count">3</property>
        </function>

count数目代表你要分几个表，3就是三个表，和schema.xml的数量一致，后端数据库为testdb2

其余的配置就和读写分离一样就行

然后启动mycat

我们要在testdb2数据库里新建三个表，t_order1，t_order2，t_order3

CREATE TABLE `t_order1` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `name` varchar(255) NOT NULL,
  `t_user_id` int(11) NOT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=10 DEFAULT CHARSET=utf8;
CREATE TABLE `t_order2` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `name` varchar(255) NOT NULL,
  `t_user_id` int(11) NOT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=10 DEFAULT CHARSET=utf8;
CREATE TABLE `t_order3` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `name` varchar(255) NOT NULL,
  `t_user_id` int(11) NOT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=10 DEFAULT CHARSET=utf8;