<!—实现两张表的一对一关系查询映射 -->
<select id=”query” resultMap=”ws2”>
select w.*,h.id husid,h.name hname,h,age hage from tb_wife w left join tb_husband h on w.hid=h.id
</select>
<resultMap type=”Wife” id=”ws2”>
<id property=”id” column=”id”/>
<result property=”name” column=”name”/>
<result property=”hobby” column=”hobby”/>
<!—嵌套对象，通过联结查询获取结果 -->
<association property=”husband” javaType=”Husband”>
<id property=”id” column=”husid”/>
<result property=”name” column=”hname”/>
<result property=”age” column=”hage”/>
</association>
</resultMap>

<select id=”query1” resultMap=”myhs2”>select h.*,c.id cid,c.name cname,c.infant from tb_husband h left join tb_child c on h.id=c.hid
</select>
<resultMap type=”Husband” id=”myhs2”>
<id property=”id” column=”id”/>
<result property=”name” column=”name”/>
<result property=”age” column=”age”/>
<!-- 嵌套集合-->
<collection property=”childs” ofType=”Child”><id property=”id” column=”cid”/><result property=”name” column=”cname”/><result property=”infant” column=”infant”/></collection>
<resultMap>

<select id=”query” parameterType=”int” resultMap=”mp1”>select s.*,st.id stid,st.days,t.id teaid,t.name tname from tb_student s left join tb_studentrelation st on s.id=st.sid left join tb_teacher t on t.id=st.tid where s.id=#{id}
</select>
<!-- 多对多的中间表的关系-->
<resultMap type=”Student” id=”mp1”>
<id property=”id” column=”id”/>
<result property=”name” column=”name”/>
<!--和中间表存在一对多-->
<collection property=”list” ofType=”StudentRelation”><id property=”id” column=”stid”/><result property=”days” column=”days”/><!-- 中间表和教师表存在多对一--><association property=”teacher” javaType=”Teacher”><id property=”id” column=”teaid”/><result property=”name” column=”tname”/></association></collection>
<resultMap>