首页查询优化

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

@@ -4,8 +4,9 @@
 
     <!--查找指定短剧的目录  按照顺序数字升序-->
     <select id="findByCourseId" resultType="com.sqx.modules.course.entity.CourseDetails">
-        select c.*,
-               cc.isGood
+        select
+            c.*,
+            ifnull(cc.isGood,0) as isGood
         from course_details c
         left join (select course_details_id,count(*) isGood from course_collect where user_id=#{userId} and classify=2 group by course_details_id) cc on c.course_details_id = c.course_details_id
         where c.course_id=#{id}  order by c.sort asc
@@ -37,7 +38,7 @@
                c.advertising,
                c.view_count as viewCount,
                c.play_complete_count as playCompleteCount,
-               cc.isGood
+               ifnull(cc.isGood,0) as isGood
         from course_details c
         left join (select course_details_id,count(*) as isGood from course_collect where user_id=#{userId} and classify=2 group by course_details_id) cc on cc.course_details_id = c.course_details_id
         where c.course_id=#{id}  order by c.sort asc