<!-- 多表连接查询 -->
<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper
PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
"http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.abc.dao.ICountryDao">
<!-- 多表连接查询 -->
<!-- 定义结果映射关系 -->
<resultMap type="Country" id="countryMap">
<id column="cid" property="cid"/>
<result column="cname" property="cname"/>
<!-- ofType解释为element of type ,元素类型 -->
<collection property="ministers" ofType="Minister">
<id column="mid" property="mid"/>
<result column="mname" property="mname"/>
</collection>
</resultMap>
<select id="selectCountryById" resultMap="countryMap">
select cid,cname,mid,mname
from country,minister
where cid=countryId and cid=#{xxx}
</select>
</mapper>
<mapper namespace="com.abc.dao.ICountryDao">
<!-- 多表单独查询 -->
<select id="selectMinisterByCountry" resultType="Minister">
select mid,mname from minister where countryId=#{ooo}
</select>
<!-- 定义结果映射关系 -->
<resultMap type="Country" id="countryMap">
<id column="cid" property="cid"/>
<result column="cname" property="cname"/>
<!-- ofType解释为element of type ,元素类型 -->
<collection property="ministers"
ofType="Minister"
select="selectMinisterByCountry"
column="cid"/>
</resultMap>
<select id="selectCountryById" resultMap="countryMap">
select cid,cname from country where cid=#{xxx}
</select>
</mapper>