one2one

多表连接

<mapper namespace="com.abc.dao.IHusbandDao">

    <!-- 多表连接查询 -->

    <!-- 定义结果映射关系 -->
    <resultMap type="Husband" id="husbandMap">
        <id column="hid" property="hid" />
        <result column="hname" property="hname" />
        <association property="wife" javaType="Wife">
            <id column="wid" property="wid" />
            <result column="wname" property="wname" />
        </association>
    </resultMap>

    <select id="selectHusbandById" resultMap="husbandMap">
        select hid,hname,wid,wname
        from husband,wife
        where wid=wifeId and hid=#{xxx}
    </select>

</mapper>

 

多表单独

<mapper namespace="com.abc.dao.IHusbandDao">

    <!-- 多表单独查询 -->

    <select id="selectWifeByHusband" resultType="Wife">
        select wid,wname from wife where wid=#{jjj}
    </select>

    <!-- 定义结果映射关系 -->
    <resultMap type="Husband" id="husbandMap">
        <id column="hid" property="hid" />
        <result column="hname" property="hname" />
        <association property="wife" 
                     javaType="Wife"
                     select="selectWifeByHusband"
                     column="wifeId"/>
    </resultMap>

    <select id="selectHusbandById" resultMap="husbandMap">
        select hid,hname,wifeId from husband where hid=#{xxx}
    </select>

</mapper>

多表连接2

    <!-- 多表连接查询 -->

    <!-- 定义结果映射关系 -->
    <resultMap type="Husband" id="husbandMap">
        <id column="hid" property="hid" />
        <result column="hname" property="hname" />
        <association property="wife" javaType="Wife">
            <id column="wid" property="wid" />
            <result column="wname" property="wname" />
        </association>
    </resultMap>

    <select id="selectHusbandById" resultMap="husbandMap">
        select hid,hname,wid,wname
        from husband,wife
        where wid=hid and hid=#{xxx}
    </select>

 

多表单独2

<mapper namespace="com.abc.dao.IHusbandDao">

    <!-- 多表单独查询 -->

    <select id="selectWifeByHusband" resultType="Wife">
        select wid,wname from wife where wid=#{jjj}
    </select>

    <!-- 定义结果映射关系 -->
    <resultMap type="Husband" id="husbandMap">
        <id column="hid" property="hid" />
        <result column="hname" property="hname" />
        <association property="wife" 
                     javaType="Wife"
                     select="selectWifeByHusband"
                     column="hid"/>
    </resultMap>

    <select id="selectHusbandById" resultMap="husbandMap">
        select hid,hname from husband where hid=#{xxx}
    </select>

</mapper>