优化课程视频查询，添加视频时长数据统计限定为学生身份

app/controllers/courses_controller.rb

@@ -103,25 +103,37 @@ class CoursesController < ApplicationController
   end
 
   def course_videos
-    videos = @course.course_videos
+    course_videos = @course.course_videos
+    course_videos = course_videos.joins("
+                    JOIN videos ON course_videos.video_id = videos.id
+                    LEFT JOIN (
+                      SELECT watch_course_videos.course_video_id,
+                             SUM(watch_course_videos.total_duration) AS total_duration,
+                             count(watch_course_videos.course_video_id) AS count 
+                      FROM watch_course_videos
+                      JOIN course_videos ON watch_course_videos.course_video_id = course_videos.id AND watch_course_videos.end_at IS NOT NULL
+                      JOIN course_members ON course_members.user_id = watch_course_videos.user_id AND course_members.course_id = #{@course.id} AND role = 4
+                      WHERE course_videos.course_id = #{@course.id}
+                      GROUP BY watch_course_videos.course_video_id
+                    ) AS watch_courses ON watch_courses.course_video_id = course_videos.id
+                  ").where("((videos.transcoded = TRUE OR videos.user_id = #{current_user.id}) OR course_videos.is_link = TRUE)")
+
     @video_module = @course.course_modules.find_by(module_type: "video")
+    
     if params[:category_id].present? && params[:category_id].to_i != 0
       @category = @video_module&.course_second_categories.find_by(id: params[:category_id])
       tip_exception("子目录id有误") if !@category.present?
-      videos = videos.where(course_second_category_id: params[:category_id].to_i)
+      course_videos = course_videos.where(course_second_category_id: params[:category_id].to_i)
     end
 
-    videos = custom_sort(videos, params[:sort_by], params[:sort_direction])
+    course_videos = custom_sort(course_videos, params[:sort_by], params[:sort_direction])
+
+    course_videos = course_videos.includes(video: [user: :user_extension], user: :user_extension)
 
-    #sql = "left join videos on videos.id=course_videos.video_id AND (videos.transcoded=1 OR videos.user_id = #{current_user.id})"
-    #@videos = paginate videos.joins(sql).includes(video: [user: :user_extension], user: :user_extension)
-    videos = videos.includes(video: [user: :user_extension],user: :user_extension).select("course_videos.id, course_videos.title, course_videos.link, course_videos.user_id")
-    videos = videos.where(videos: {transcoded: true})
-                 .or(videos.where(videos: {user_id: current_user.id}))
-                 .or(videos.where(course_videos: {is_link: true}))
-    @count = videos.count("course_videos.id")
+    @count = course_videos.count("course_videos.id")
     logger.info("#######count:#{@count}")
-    @videos = paginate videos
+    course_videos = course_videos.select("IFNULL(watch_courses.total_duration, 0) AS total_duration, IFNULL(watch_courses.count,0) AS count, course_videos.video_id, course_videos.title, course_videos.is_link, course_videos.user_id")
+    @videos = paginate course_videos
   end
 
   def delete_course_video

app/views/courses/course_videos.json.jbuilder

@@ -10,8 +10,8 @@ json.videos @videos do |video|
     json.user_login user&.login
   else
     json.partial! 'users/videos/video', locals: { video: video.video }
-    json.total_time video.watch_course_videos.sum(:total_duration).round(0)
-    json.people_num video.watch_course_videos.count(:user_id)
+    json.total_time video['total_duration'].round(0)
+    json.people_num video['count']
   end
 end