代码/restaurants/src/main/resources/mapper/CommentMapper.xml

微信扫码关注公众号，代码整理好后第一时间通知你。

<?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.mall.mapper.CommentMapper">

    <select id="getComment" resultType="string">
         select
          item_id
        from comment
        order by score
    </select>


    <resultMap id="TopType" type="HashMap">
        <result column="question_type" property="typeName" />
        <result column="type_count" property="typeCount" />
    </resultMap>

    <select id="countErrorQuestionLevel" resultMap="TopType">
		select
		count(*) value,
		q.title as name
		from
			comment e
		left join
			item q
			on  e.item_id =q.id
		GROUP BY
            name
	</select>


    <select id="getCommentList" resultType="com.mall.vo.CommentVo">
		SELECT
			c.comment,
			c.score,
			u.uname,
			i.title
		FROM
			COMMENT c
		LEFT JOIN USER u ON c.user_id = u.id
		LEFT JOIN item i ON c.item_id = i.id
	</select>
</mapper>