首页查询优化

src/main/resources/mapper/course/CourseDao.xml

@@ -31,39 +31,19 @@
         c.course_type as courseType,
         c.banner_id as bannerId,
         b.name as bannerName,
-        (select sum(cd.view_count) from course_details cd where cd.course_id = c.course_id ) as viewCounts,
+        0 as viewCounts,
         c.dy_img_id as dyImgId,
         c.dy_course_id as dyCourseId,
         c.wx_course_id as wxCourseId,
         c.wx_show as wxShow,
         c.dy_show as dyShow,
         c.sort,
-        (select sum(good_num) from course_details d where d.course_id=c.course_id ) as goodNum,
-        (select count(*) from course_details d where d.course_id=c.course_id ) as courseDetailsCount,
-          <if test="userId!=null">
-              (
-              SELECT
-              cc.course_details_id
-              FROM
-              course_collect cc
-              WHERE
-              cc.course_id = c.course_id
-              AND cc.classify = 3
-              and cc.user_id = #{userId}
-              ORDER BY
-              cc.update_time desc
-              LIMIT 1
-              ) AS courseDetailsId,
-          </if>
-          <if test="userId==null">
-              null AS courseDetailsName,
-              null AS courseDetailsId,
-          </if>
-
-        (select count(*) from course_collect d where d.course_id=c.course_id
-        and date_format(create_time,'%Y-%m-%d')>=date_format(#{startTime},'%Y-%m-%d') and
-        date_format(create_time,'%Y-%m-%d')&lt;=date_format(#{endTime},'%Y-%m-%d') ) as weekGoodNum,
-        (select count(*) from course_details cd where c.course_id=cd.course_id and cd.good=1 ) as isRecommend
+        0 as goodNum,
+        0 as courseDetailsCount,
+        null AS courseDetailsName,
+        null AS courseDetailsId,
+        0 as weekGoodNum,
+        0 as isRecommend
         FROM
         course AS c
         LEFT JOIN course_classification AS cc ON c.classify_id = cc.classification_id
@@ -113,6 +93,8 @@
         <if test="dyCourse!=null">
             and c.dy_status=4
         </if>
+        order by c.sort asc,c.create_time desc
+        <!--
         <if test="sort==null">
             order by c.sort asc
         </if>
@@ -122,6 +104,7 @@
         <if test="sort!=null and sort==2">
             order by weekGoodNum desc
         </if>
+        -->
     </select>
 
     <select id="selectCourseAdmin" resultType="Map">
@@ -241,6 +224,8 @@
         <if test="dyCourse!=null">
             and c.dy_status=4
         </if>
+        order by c.sort asc,c.create_time desc
+        <!--
         <if test="sort==null">
             order by c.sort asc,c.create_time desc
         </if>
@@ -250,6 +235,7 @@
         <if test="sort!=null and sort==2">
             order by weekGoodNum desc
         </if>
+        -->
     </select>
 
     <select id="selectCourseTitle" resultType="Map">