schema.xml管理着MyCat的逻辑库、表、分片规则、DataNode以及DataSource。弄懂这些配置,是正确使用MyCat的前提。

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

    <schema name="TESTDB" checkSQLschema="false" sqlMaxLimit="100">
        <!-- auto sharding by id (long) -->
        <table name="travelrecord" dataNode="dn1,dn2,dn3" rule="auto-sharding-long" />

        <!-- global table is auto cloned to all defined data nodes ,so can join
            with any table whose sharding node is in the same data node -->
        <table name="company" primaryKey="ID" type="global" dataNode="dn1,dn2,dn3" />
        <table name="goods" primaryKey="ID" type="global" dataNode="dn1,dn2" />
        <!-- random sharding using mod sharind rule -->
        <table name="hotnews" primaryKey="ID" autoIncrement="true" dataNode="dn1,dn2,dn3"
               rule="mod-long" />
        <!-- <table name="dual" primaryKey="ID" dataNode="dnx,dnoracle2" type="global"
            needAddLimit="false"/> <table name="worker" primaryKey="ID" dataNode="jdbc_dn1,jdbc_dn2,jdbc_dn3"
            rule="mod-long" /> -->
        <table name="employee" primaryKey="ID" dataNode="dn1,dn2"
               rule="sharding-by-intfile" />
        <table name="customer" primaryKey="ID" dataNode="dn1,dn2"
               rule="sharding-by-intfile">
            <childTable name="orders" primaryKey="ID" joinKey="customer_id"
                        parentKey="id">
                <childTable name="order_items" joinKey="order_id"
                            parentKey="id" />
            </childTable>
            <childTable name="customer_addr" primaryKey="ID" joinKey="customer_id"
                        parentKey="id" />
        </table>
        <!-- <table name="oc_call" primaryKey="ID" dataNode="dn1$0-743" rule="latest-month-calldate"
            /> -->
    </schema>
    <!-- <dataNode name="dn1$0-743" dataHost="localhost1" database="db$0-743"
        /> -->
    <dataNode name="dn1" dataHost="localhost1" database="db1" />
    <dataNode name="dn2" dataHost="localhost1" database="db2" />
    <dataNode name="dn3" dataHost="localhost1" database="db3" />
    <!--<dataNode name="dn4" dataHost="sequoiadb1" database="SAMPLE" />
     <dataNode name="jdbc_dn1" dataHost="jdbchost" database="db1" />
    <dataNode    name="jdbc_dn2" dataHost="jdbchost" database="db2" />
    <dataNode name="jdbc_dn3"     dataHost="jdbchost" database="db3" /> -->
    <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="123456">
            <!-- can have multi read hosts -->
            <readHost host="hostS2" url="192.168.1.200:3306" user="root" password="xxx" />
        </writeHost>
        <writeHost host="hostS1" url="localhost:3316" user="root"
                   password="123456" />
        <!-- <writeHost host="hostM2" url="localhost:3316" user="root" password="123456"/> -->
    </dataHost>
    <!--
        <dataHost name="sequoiadb1" maxCon="1000" minCon="1" balance="0" dbType="sequoiadb" dbDriver="jdbc">
        <heartbeat>         </heartbeat>
         <writeHost host="hostM1" url="sequoiadb://1426587161.dbaas.sequoialab.net:11920/SAMPLE" user="jifeng"     password="jifeng"></writeHost>
         </dataHost>

      <dataHost name="oracle1" maxCon="1000" minCon="1" balance="0" writeType="0"     dbType="oracle" dbDriver="jdbc"> <heartbeat>select 1 from dual</heartbeat>
        <connectionInitSql>alter session set nls_date_format='yyyy-mm-dd hh24:mi:ss'</connectionInitSql>
        <writeHost host="hostM1" url="jdbc:oracle:thin:@127.0.0.1:1521:nange" user="base"     password="123456" > </writeHost> </dataHost>

        <dataHost name="jdbchost" maxCon="1000"     minCon="1" balance="0" writeType="0" dbType="mongodb" dbDriver="jdbc">
        <heartbeat>select     user()</heartbeat>
        <writeHost host="hostM" url="mongodb://192.168.0.99/test" user="admin" password="123456" ></writeHost> </dataHost>

        <dataHost name="sparksql" maxCon="1000" minCon="1" balance="0" dbType="spark" dbDriver="jdbc">
        <heartbeat> </heartbeat>
         <writeHost host="hostM1" url="jdbc:hive2://feng01:10000" user="jifeng"     password="jifeng"></writeHost> </dataHost> -->

    <!-- <dataHost name="jdbchost" maxCon="1000" minCon="10" balance="0" dbType="mysql"
        dbDriver="jdbc"> <heartbeat>select user()</heartbeat> <writeHost host="hostM1"
        url="jdbc:mysql://localhost:3306" user="root" password="123456"> </writeHost>
        </dataHost> -->
</mycat:schema>