mycat的入门教程（二）

在上篇教程中初步介绍了mycat的使用，接下来搭建一个拆分的策略（取模还是按区间划分等）的入门教程来实现一个分库分表的功能

三张表users和test，三个数据库test，test2，dmeo（三个库在一个数据库实例上）

users表被分割到test,test2中存储。

test在dmeo中存储。

创建三个数据库，并创建对应的表

-- ----------------------------
-- Table structure for `users`
-- ----------------------------
DROP TABLE IF EXISTS `users`;
CREATE TABLE `users` (
`id` bigint(20) NOT NULL AUTO_INCREMENT,
`user_name` varchar(100) DEFAULT NULL,
PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=2 DEFAULT CHARSET=utf8;

DROP TABLE IF EXISTS `test`;
CREATE TABLE `test` (
`id` bigint(20) NOT NULL AUTO_INCREMENT,
`name` varchar(50) NOT NULL,
`phone` varchar(11) DEFAULT NULL,
`create_time` datetime NOT NULL,
`update_time` datetime NOT NULL,
PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=3 DEFAULT CHARSET=utf8 COMMENT='用户测试表';

配置如下所示：

（1）rule.xml

<?xml version="1.0" encoding="UTF-8"?>
<!-- - - Licensed under the Apache License, Version 2.0 (the "License");
- you may not use this file except in compliance with the License. - You
may obtain a copy of the License at - - http://www.apache.org/licenses/LICENSE-2.0 - - Unless required by applicable law or agreed to in writing, software -
distributed under the License is distributed on an "AS IS" BASIS, - WITHOUT
WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. - See the
License for the specific language governing permissions and - limitations
under the License. -->
<!DOCTYPE mycat:rule SYSTEM "rule.dtd">
<mycat:rule xmlns:mycat="http://io.mycat/">
<tableRule name="rule1">
<rule>
<columns>id</columns>
<algorithm>mod-long</algorithm>
</rule>
</tableRule>
<function name="mod-long" class="io.mycat.route.function.PartitionByMod">
<!-- how many data nodes -->
<property name="count">2</property>
</function>
</mycat:rule>

(2)schema.xml

<?xml version="1.0"?>
<!DOCTYPE mycat:schema SYSTEM "schema.dtd">
<mycat:schema xmlns:mycat="http://io.mycat/">

<schema name="TESTDB" checkSQLschema="false" sqlMaxLimit="100">
<table name="test" primaryKey="ID" type="global"  dataNode="dn1" />
<table name="users" primaryKey="ID"  dataNode="dn2,dn3" rule="rule1"/>
</schema>

<dataNode name="dn1" dataHost="localhost1" database="dmeo" />
<dataNode name="dn2" dataHost="localhost1" database="test" />
<dataNode name="dn3" dataHost="localhost1" database="test2" />

<dataHost name="localhost1" maxCon="1000" minCon="10" balance="0" writeType="0" dbType="mysql" dbDriver="native" switchType="1"  slaveThreshold="100">
<heartbeat>select user()</heartbeat>
<!-- can have multi write hosts -->
<writeHost host="hostM1" url="localhost:3306" user="root" password="root">
<!-- can have multi read hosts -->
<readHost host="hostS2" url="127.0.0.1:3306" user="root" password="root" />
</writeHost>
</dataHost>
</mycat:schema>

(3)server.xml和wrapper.conf这两文件和mycat的入门教程（一）中配置一样，没有发生改变

在逻辑数据库TESTDB的users表中插入三条数据，如下显示：



对应的test和test2两个数据库中的数据，如下显示：





通过上面的数据来看，根据实际的路由策略进行了分表，对数据实现了分库分表！