repair_reporting_system_api/src/main/resources/mapper/RepairsBuildRoomMapper.xml

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://www.mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.chuanghai.repair.mapper.RepairsBuildRoomMapper">
    <resultMap id="BaseResultMap" type="com.chuanghai.repair.entity.RepairsRoom">
        <!--
          WARNING - @mbg.generated
        -->
        <id column="room_id" property="roomId" jdbcType="INTEGER"/>
        <result column="room_name" property="roomName" jdbcType="VARCHAR"/>
        <!--        房间与楼栋之间是  N:1 关系-->
        <association  property="repairsFloor"  javaType="com.chuanghai.repair.entity.RepairsFloor">
            <id column="floor_id" property="floorId"></id>
            <result column="floor_name" property="floorName" jdbcType="VARCHAR"/>
            <association  property="repairsBuild"  javaType="com.chuanghai.repair.entity.RepairsBuild">
                <id column="build_id" property="buildId"></id>
                <result column="build_name" property="buildName" jdbcType="VARCHAR"/>
            </association >
        </association >
    </resultMap>

<!--    查询所有宿舍信息-->
    <select id="queryAllBuildRoom" resultMap="BaseResultMap">
        select * from repairs_build bu,repairs_floor fl, repairs_room ro where bu.build_id = fl.build_id and fl.floor_id = ro.floor_id
    </select>
</mapper>