toby-yezhu/yezhu-api/src/main/resources/mapper/messageboard/MessageDao.xml

<?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.kioor.messageboard.dao.MessageDao">

    <select id="getList" resultType="com.kioor.messageboard.dto.MessageDTO">
        select tm.*,tmb.housing_estate_id as housingEstateId, tuhe.remark as roomName
        from tb_messages tm
        left join tb_message_board  tmb on tm.message_board_id = tmb.id
        left join tb_user tu on tm.edit_user = tu.id
        left join tb_user_housing_estate tuhe on tu.id = tuhe.user_id
        <where>
            <if test="messageBoardId != null">
                and tm.message_board_id = #{messageBoardId}
            </if>
            <if test="housingEstateId != null">
                and tmb.housing_estate_id = #{housingEstateId}
            </if>
        </where>
        order by tm.edit_time asc
    </select>

    <select id="get" resultType="com.kioor.messageboard.dto.MessageDTO">
        select tm.*,tmb.housing_estate_id as housingEstateId, tuhe.remark as roomName
        from tb_messages tm
        left join tb_message_board  tmb on tm.message_board_id = tmb.id
        left join tb_user tu on tm.edit_user = tu.id
        left join tb_user_housing_estate tuhe on tu.id = tuhe.user_id
        where tm.id = #{id}
    </select>
</mapper>