diff --git a/app/controllers/discusses_controller.rb b/app/controllers/discusses_controller.rb
index f100ac233..3b987be51 100644
--- a/app/controllers/discusses_controller.rb
+++ b/app/controllers/discusses_controller.rb
@@ -10,17 +10,20 @@ class DiscussesController < ApplicationController
     if current_user.admin?
       @disscuss_count = Discuss.where(:dis_id => @container.id, :dis_type => @container.class.to_s, :root_id => nil).count
       disscusses = Discuss.where(:dis_id => @container.id, :dis_type => @container.class.to_s,
-                                             :root_id => nil).joins(challenge: :games)
-                       .where("discusses.user_id = games.user_id").select("discusses.*, games.identifier")
+                                             :root_id => nil)
     else
       disscusses = Discuss.where("dis_id = :dis_id and dis_type = :dis_type and root_id is null and
                                       (discusses.hidden = :hidden or discusses.user_id = :user_id)",
                                  {dis_id: @container.id, dis_type: @container.class.to_s, hidden: false, user_id: current_user.id})
-                       .joins(challenge: :games).where("discusses.user_id = games.user_id").select("discusses.*, games.identifier")
       @disscuss_count = disscusses.count("discusses.id")
     end
-    @discusses = disscusses.limit(LIMIT).includes(:user, :praise_treads).offset(offset)
     @manger = @container.has_manager?(current_user)
+    if @manger
+      @discusses = disscusses.limit(LIMIT).joins("left join games on discusses.challenge_id = games.challenge_id and discusses.user_id = games.user_id")
+                       .select("discusses.*, games.identifier").includes(:user, :praise_treads).offset(offset)
+    else
+      @discusses = disscusses.limit(LIMIT).includes(:user, :praise_treads).offset(offset)
+    end
 
     @current_user = current_user
   end
diff --git a/app/controllers/graduation_tasks_controller.rb b/app/controllers/graduation_tasks_controller.rb
index 9b62f7dbd..fd6a1d859 100644
--- a/app/controllers/graduation_tasks_controller.rb
+++ b/app/controllers/graduation_tasks_controller.rb
@@ -55,6 +55,8 @@ class GraduationTasksController < ApplicationController
     page = params[:page] || 1
     limit = params[:limit] || 20
     @work = @task.graduation_works.where(user_id: current_user.id)
+    @students = @course.students
+    @assign_power = @user_course_identity < Course::STUDENT && @task.cross_comment && @task.comment_status == 2
     #end_time @task.allow_late ? @task.late_time : @task.end_time
     # 任务发布的情况下： 是老师身份或者任务已截止的情况下公开任务了作品设置的学生也能查看其他人的作品
     if @task.published? && (@user_course_identity < Course::STUDENT ||
@@ -123,8 +125,6 @@ class GraduationTasksController < ApplicationController
       @work_count = @work_list.count
       @work_excel = @work_list
       @work_list = @work_list.page(page).per(limit)
-      @students = @course.students
-      @assign_power = @user_course_identity < Course::STUDENT && @task.cross_comment && @task.comment_status == 2
 
       if params[:format] == "xlsx"
         complete_works = @work_excel.where("work_status > 0").size
diff --git a/app/controllers/shixuns_controller.rb b/app/controllers/shixuns_controller.rb
index c237da5e2..e4d18316e 100644
--- a/app/controllers/shixuns_controller.rb
+++ b/app/controllers/shixuns_controller.rb
@@ -129,7 +129,7 @@ class ShixunsController < ApplicationController
 				select m.user_id, u.login, u.lastname, m.updated_at,
 					(select sum(cost_time) from games g where g.myshixun_id = m.id) as time,
 					(select sum(final_score) from games g where g.myshixun_id = m.id) as score
-				from (myshixuns m join users u on m.user_id = u.id) where m.shixun_id = #{@shixun.id} and m.status = 1
+				from (users u left join myshixuns m on m.user_id = u.id) where m.shixun_id = #{@shixun.id} and m.status = 1
 				order by score desc, time asc limit 10
 			"
 			@myshixuns = Myshixun.find_by_sql(sql)
diff --git a/app/controllers/subjects_controller.rb b/app/controllers/subjects_controller.rb
index 4fa818099..46f3b4850 100644
--- a/app/controllers/subjects_controller.rb
+++ b/app/controllers/subjects_controller.rb
@@ -25,13 +25,13 @@ class SubjectsController < ApplicationController
         @subjects = Subject.find_by_sql("SELECT subjects.id, subjects.user_id, subjects.name, subjects.stages_count, subjects.repertoire_id, subjects.status,
                       subjects.shixuns_count, sum(shixuns.myshixuns_count) AS myshixun_member_count FROM subjects join stage_shixuns
                       on stage_shixuns.subject_id = subjects.id join shixuns on shixuns.id = stage_shixuns.shixun_id where
-                      'subjects'.'hidden' = 0 AND `subjects`.`status` = 2 AND `subjects`.`name` like '%#{search}%'
-                      AND `subjects`.`repertoire_id` = #{select} GROUP BY subjects.id ORDER BY myshixun_member_count DESC")
+                      subjects.hidden = 0 AND subjects.status = 2 AND subjects.name like '%#{search}%'
+                      AND subjects.repertoire_id = #{select} GROUP BY subjects.id ORDER BY myshixun_member_count DESC")
       else
         @subjects = Subject.find_by_sql("SELECT subjects.id, subjects.user_id, subjects.name, subjects.stages_count, subjects.repertoire_id, subjects.status,
                       subjects.shixuns_count, sum(shixuns.myshixuns_count) AS myshixun_member_count FROM subjects join stage_shixuns
                       on stage_shixuns.subject_id = subjects.id join shixuns on shixuns.id = stage_shixuns.shixun_id where
-                      `subjects`.`hidden` = 0 AND `subjects`.`status` = 2 AND `subjects`.`name` like '%#{search}%'
+                      subjects.hidden = 0 AND subjects.status = 2 AND subjects.name like '%#{search}%'
                       GROUP BY subjects.id ORDER BY myshixun_member_count DESC")
       end
     else
diff --git a/app/views/discusses/_discuss.json.jbuilder b/app/views/discusses/_discuss.json.jbuilder
index ee9484131..400798150 100644
--- a/app/views/discusses/_discuss.json.jbuilder
+++ b/app/views/discusses/_discuss.json.jbuilder
@@ -7,10 +7,10 @@ json.time time_from_now(discuss.created_at)
 json.position discuss.position
 json.shixun_id discuss.dis_id
 json.hidden discuss.hidden
-json.manage current_user.manager_of_shixun?(container)
+json.manage @manger
 json.reward discuss.reward
 #json.game_url discuss.game_url(container, current_user)
-json.game_url "/tasks/#{discuss.identifier}" if @manger
+json.game_url "/tasks/#{discuss.identifier}" if @manger && !children
 # 主贴和回复有一些不同点
 if discuss.parent_id
   json.can_delete discuss.can_deleted?(current_user)
diff --git a/app/views/discusses/index.json.jbuilder b/app/views/discusses/index.json.jbuilder
index 1b7a95eb3..7ddfb31fb 100644
--- a/app/views/discusses/index.json.jbuilder
+++ b/app/views/discusses/index.json.jbuilder
@@ -1,8 +1,8 @@
 json.disscuss_count @disscuss_count
 json.all @current_user.admin?
 json.comments @discusses do |discuss|
-  json.partial! 'discusses/discuss', locals: { discuss: discuss, container: @container, current_user: @current_user }
+  json.partial! 'discusses/discuss', locals: { discuss: discuss, container: @container, current_user: @current_user,  children: false}
   json.children discuss.child_discuss(current_user) do |c_d|
-    json.partial! 'discusses/discuss', locals: { discuss: c_d, container: @container, current_user: @current_user }
+    json.partial! 'discusses/discuss', locals: { discuss: c_d, container: @container, current_user: @current_user, children: true }
   end
 end