RealWorld/realworld/src/main/resources/mybatis/mapper/user/ArticleMapper.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.dbs.realworld.mapper.ArticleMapper">
  
   <insert id="insertArticle" parameterType="ArticleDTO" useGeneratedKeys="true" keyProperty="id">
        <![CDATA[
            INSERT 
              INTO article_mst
                   ( user_id,   title, subtitle, content, create_datetime, tags	)
            VALUES ( #{writerId}, #{title},  #{subtitle}, #{content}, #{created}, #{tags} )
        ]]>
    </insert>

    <update id="updateArticle" parameterType="ArticleDTO">
      <![CDATA[
          UPDATE	article_mst
            SET	update_datetime = NOW()
      ]]>
      <if test='title != null'>
        , title = #{title}
      </if>
      <if test='subtitle != null'>
        , subtitle = #{subtitle}
      </if>
      <if test='content != null'>
        , content = #{content}
      </if>
      <if test='tags != null'>
        , tags = #{tags}
      </if>
        <![CDATA[
          WHERE id = #{id}
        ]]>	
    </update>

    <!-- 
      커서 기반 페이징 
      - articleId는 커서 역할
        - -1은 초깃값이며 이 경우 최초의 페이지 데이터들을 조회
      - feed는 현재 사용자가 보고 있는 feed
        - 'your-feed' 혹은 'global-feed' 값을 가지며 기본 값은 'global-feed'
      - 시간별 최신 정렬 및 페이지 당 10개의 데이터 조회
    -->
    <select id="select" parameterType="hashmap" resultType="ArticleDTO">
      <![CDATA[
        SELECT
          AR.id               AS id,
          AR.title            AS title,
          AR.subtitle         AS subtitle,
          AR.content          AS content,
          AR.tags             AS tags,
          AR.create_datetime  AS created,
          AR.favorite_num     AS favoriteNum,
      ]]>
      <if test='userId != -1'>
        <![CDATA[
          (
              SELECT COUNT(*) FROM article_like AL 
              WHERE AL.user_id     = #{userId}
              AND   AL.article_id  = AR.id
          )                   AS favorite,
        ]]>
      </if>
      <![CDATA[
          AR.user_id          AS writerId,
          USR.name            AS writerName,
          USR.email           AS writerEmail
        FROM article_mst AR
        LEFT JOIN user_mst USR
        ON AR.user_id = USR.id
        WHERE 1=1
      ]]>
      <if test='articleId != -1'>
        <![CDATA[
          AND AR.id < #{articleId}
        ]]>
      </if>
      <if test='feed == "your-feed"'>
        <![CDATA[
          AND AR.user_id = #{userId}
        ]]>
      </if>
      <![CDATA[
        ORDER BY create_datetime DESC
        LIMIT 10
      ]]>
    </select>


     <select id="selectPagingInfo" parameterType="hashmap" resultType="hashmap">
        <![CDATA[
          SELECT 
            COUNT(*)                                 AS total,
            COUNT( IF(id < #{articleId}, 1, null) )  AS nextItemNum
          FROM article_mst AR
        ]]>
        <if test='feed == "your-feed"'>
          <![CDATA[
            WHERE     AR.user_id = #{userId}
            GROUP BY  AR.user_id
          ]]>
        </if>
     </select>


    <select id="selectAll" parameterType="ArticleDTO" resultType="ArticleDTO">
      <![CDATA[
        SELECT
          AR.id               AS id,
          AR.title            AS title,
          AR.subtitle         AS subtitle,
          AR.content          AS content,
          AR.tags             AS tags,
          AR.create_datetime  AS created,
          AR.user_id          AS writerId,
          USR.name            AS writerName,
          USR.email           AS writerEmail
        FROM article_mst AR
        LEFT JOIN user_mst USR
        ON AR.user_id = USR.id
        ORDER BY create_datetime DESC
        LIMIT 10
      ]]>
    </select>

    <select id="selectByArticleId" parameterType="int" resultType="ArticleDTO">
      <![CDATA[
        SELECT
          AR.id               AS id,
          AR.title            AS title,
          AR.subtitle         AS subtitle,
          AR.content          AS content,
          AR.tags             AS tags,
          AR.create_datetime  AS created,
          AR.user_id          AS writerId,
          USR.name            AS writerName,
          USR.email           AS writerEmail
        FROM article_mst AR
        LEFT JOIN user_mst USR
        ON AR.user_id = USR.id
        WHERE AR.id = #{articleId}
      ]]>
    </select>

    <delete id="deleteByArticleId" parameterType="int">
        <![CDATA[
            DELETE FROM article_mst WHERE id = #{articleId}
        ]]>
    </delete>

    <insert id="insertFavorite" parameterType="hashmap">
        <![CDATA[
            INSERT IGNORE INTO article_like 
              ( user_id, article_id	)
            VALUES 
              ( #{userId}, #{articleId} )
        ]]>
    </insert>

    <delete id="deleteFavorite" parameterType="hashmap">
        <![CDATA[
            DELETE FROM article_like
            WHERE user_id    = #{userId}
            AND   article_id = #{articleId}
        ]]>
    </delete>

    <update id="updateFavoriteNum" parameterType="int">
      <![CDATA[
          UPDATE	article_mst
             SET	favorite_num = (SELECT COUNT(*) FROM article_like WHERE article_id = #{articleId})
          WHERE   id = #{articleId}
      ]]>
    </update>
</mapper>