项目中myBatis特殊语法使用

前言：侧重于MyBatis的使用

一、myBatis一对一和对多使用

1、xml文件，巧用映射进行操作

<!--定义映射,这里包含一对多和一对一个查询-->
<resultMap id="MyMovieVo" type="com.xusj.cinema.vo.MyMovieVo">
  <result property="movieId" column="movie_id"/>
  <result property="movieName" column="movie_name"/>
  <result property="movieReleaseTime" column="movie_release_time"/>
  <result property="movieArea" column="movie_area"/>
  <result property="movieInfo" column="movie_info"/>
  <result property="movieVersion" column="movie_version"/>
  <result property="movieImg" column="movie_img"/>
  <result property="movieEname" column="movie_ename"/>
  <result property="movieScore" column="movie_score"/>
  <result property="movieStatus" column="movie_status"/>
  <result property="movieCount" column="movie_count"/>
  <result property="movieBoxOffice" column="movie_box_office"/>
  <result property="movieTime" column="movie_time"/>
  <result property="movieWantCount" column="movie_want_count"/>
  <result property="movieReleaseYear" column="movie_release_year"/>
  <result property="commentUserCount" column="comment_user_count"/>
  <!--一对一标签：理解：将column="movie_area"，当作select=这个语句中的参数，然后查询结果赋值给property-->
  <association property="movieAreaStr" column="movie_area"
               select="com.xusj.cinema.mapper.MovieMapper.selectById"/>
  <!--一对多标签：理解同上-->
  <collection property="movieImageList" column="movie_id"
              select="com.xusj.cinema.mapper.MovieMapper.selectImgList"/>
  <!--select="com.xusj.cinema.mapper.MovieMapper.selectTypeList"，这个里面是关联查询，不要思维定式-->
  <collection property="movieTypeList" ofType="com.xusj.cinema.domain.MovieType" column="movie_id"
              select="com.xusj.cinema.mapper.MovieMapper.selectTypeList"/>
</resultMap>
<!--定义sql片段-->
<sql id="selectMovieVo">
  select movie_id,
  movie_name,
  movie_release_time,
  movie_area,
  movie_info,
  movie_version,
  movie_img,
  movie_ename,
  movie_score,
  movie_status,
  movie_count,
  movie_box_office,
  movie_time,
  movie_want_count,
  movie_release_year,
  comment_user_count
  from tb_movie
</sql>

<!--返回映射结果，在里面完成一对一和一对多的查询/*使用sql片段*/-->
<select id="selectMovieToEs" resultMap="MyMovieVo">
  <include refid="selectMovieVo"/>
 </select>

当你的mapper成有多个参数的时候，{}使用大括号给不同的参数赋值

2、mapper层（每个都通过xml中select=”com.xusj.cinema.mapper.MovieMapper.selectTypeList”标签找到对应的mapper进行查询）

/***
* 查询对应的es中的数据
*
* @return {@link MyMovieVo}
* @author xusj
* <br>CreateDate 2022/5/14 15:19
*/
List<MyMovieVo> selectMovieToEs();

/***
* 根据地址查看对应的地区名称
*
* @param id
* @return {@link String}
* @author xusj
* <br>CreateDate 2022/5/14 15:24
*/
String selectById(int id);


List<MovieImage> selectImgList(int id);

List<MovieType> selectTypeList(int id);

===》更新2022.05.15

时间范围

<if test="startTime!=null">
	and DATE_FORMAT(a.create_date,'%Y-%m-%d %H:%i:%s') <![CDATA[ >= ]]>DATE_FORMAT(#{startTime},'%Y-%m-%d %H:%i:%s')
</if>
<if test="endTime!=null">
    and DATE_FORMAT(a.create_date,'%Y-%m-%d %H:%i:%s') <![CDATA[ <= ]]>DATE_FORMAT(#{endTime},'%Y-%m-%d %H:%i:%s')
</if>

// 一对多对条件mybatis 标签传参

<resultMap id="selectStoreAndChannelMap" type="com.xiangzheng.gmcserver.vo.StoreAndChannelVO">
        <result property="channelCode" column="channelCode"/>
        <result property="sysId" column="sysId"/>
        // 主要是这里{使用这个}
        <collection property="storeInfoList" column="{channelCode=channelCode,sysId=sysId}"
                    select="com.xiangzheng.gmcserver.mapper.StoresMapper.selectStoreInfo"/>
    </resultMap>