用Map来封装sql查询结果和GROUP_CONCAT函数用法

  <select id="selectList" resultMap="BaseResultMap">
    SELECT tg.id,tg.code,GROUP_CONCAT(DISTINCT tpi.name) placeNames ,GROUP_CONCAT(DISTINCT tgs.name) gridStaffNames,GROUP_CONCAT(DISTINCT tgs.tel) gridStaffTels,
    tg.grid_name,tg.short_name,tg.group_id,tg.number,tg.coordinates,tg.color,tg.center_coordinates,tg.status,tg.grid_man,tg.tel,tg.remark,tg.create_time,
    tg.create_account,tg.create_account_name,tgg.group_name groupName,tg.modify_time,tg.modify_account
    FROM t_grid tg
    LEFT JOIN t_place_grid tpg ON tg.id=tpg.grid_id
    LEFT JOIN t_place_info tpi ON tpi.id=tpg.place_id
    LEFT JOIN t_grid_group tgg ON tg.group_id=tgg.id
    LEFT JOIN t_grid_staff tgs ON tg.id=tgs.grid_id
    where tg.status != -1
    <if test="placeIdList != null">
      and tpg.place_id in
      <foreach collection="placeIdList" item="item" close=")" open="(" separator=",">
        #{item}
      </foreach>
    </if>
    <if test="searchContent != null and searchContent != ''">
      and(tgg.group_name like concat('%',#{searchContent},'%') or tgg.short_name  like concat('%',#{searchContent},'%') or tg.grid_name like concat('%',#{searchContent},'%')
      or tg.short_name like concat('%',#{searchContent},'%') or tgg.group_man like concat('%',#{searchContent},'%') or tgs.name like concat('%',#{searchContent},'%'))
    </if>
    <if test="status != null">
      and tg.status = #{status}
    </if>
    <if test="arrIds != null">
      and tg.id in
      <foreach  collection="arrIds" index="index" open="(" item="item" close=")" separator=",">
        #{item}
      </foreach>
    </if>
    group by tg.id
    order by tg.create_time desc,tg.grid_name desc
  </select>

  <select id="getFaWaterLevelList" resultType="java.util.Map">
    SELECT water_level `value`,DATE_FORMAT(upload_time, '%Y-%m-%d %H:%i:%s')as `date`
    FROM t_fa_water_level_pressure_sensor_data
    where device_id = #{deviceId} and `upload_time` > DATE_ADD(date(now()),INTERVAL -29 day) and del_flag = 0
    order by upload_time asc
  </select>

DATE_FORMAT 用法：参考链接 https://www.w3school.com.cn/sql/func_date_format.asp

DATE_ADD 用法：参考链接https://blog.csdn.net/weixin_39921821/article/details/108095060