diff --git a/app/controllers/homework_commons_controller.rb b/app/controllers/homework_commons_controller.rb
index 2fcf421f4..d49dac853 100644
--- a/app/controllers/homework_commons_controller.rb
+++ b/app/controllers/homework_commons_controller.rb
@@ -106,11 +106,10 @@ class HomeworkCommonsController < ApplicationController
 
     student_works = @homework.all_works
     @all_member_count = student_works.size
-    logger.info("##########__________@homework.publish_time______________#############{@homework.publish_time}")
-    if @homework.publish_time.blank? || (@homework.publish_time > Time.now)
+
+    if @homework.publish_time.nil? || (@homework.publish_time > Time.now)
       @student_works = []
-      if params[:format] == "xlsx" || params[:format] == "zip"
-        logger.info("##########__________params[:format]______________#############{params[:format]}")
+      if (params[:format] == "xlsx") || (params[:format] == "zip")
         normal_status(-1,"作业未发布")
       end
     else
@@ -198,7 +197,7 @@ class HomeworkCommonsController < ApplicationController
       end
 
       if params[:format] == "xlsx"
-        complete_works = @work_excel.where("work_status > 0").size
+        complete_works = @work_excel.present? ? @work_excel.where("work_status > 0").size : 0
         if @user_course_identity >= Course::STUDENT
           tip_exception(403, "无权限操作")
         elsif complete_works == 0
@@ -218,8 +217,13 @@ class HomeworkCommonsController < ApplicationController
         if @user_course_identity >= Course::STUDENT
           tip_exception(403, "无权限操作")
         else
-          zip_works = @work_excel.where("work_status > 0")
-          status = checkfileSize(zip_works)
+          if @work_excel.present?
+            zip_works = @work_excel&.where("work_status > 0")
+            status = checkfileSize(zip_works)
+          else
+            status = -1
+          end
+
           if status == 0
             respond_to do |format|
               format.zip{
diff --git a/app/jobs/exercise_publish_notify_job.rb b/app/jobs/exercise_publish_notify_job.rb
index 563f6ceb0..f68a68c00 100644
--- a/app/jobs/exercise_publish_notify_job.rb
+++ b/app/jobs/exercise_publish_notify_job.rb
@@ -6,6 +6,7 @@ class ExercisePublishNotifyJob < ApplicationJob
     exercise = Exercise.find_by(id: exercise_id)
     return if exercise.blank?
     user = exercise.user
+    course = exercise.course
 
     if group_ids.present?
       students = course.students.where(course_group_id: group_ids)
diff --git a/app/jobs/graduation_task_publish_notify_job.rb b/app/jobs/graduation_task_publish_notify_job.rb
index 92346ab27..16f5893ae 100644
--- a/app/jobs/graduation_task_publish_notify_job.rb
+++ b/app/jobs/graduation_task_publish_notify_job.rb
@@ -5,6 +5,8 @@ class GraduationTaskPublishNotifyJob < ApplicationJob
   def perform(graduation_task_id)
     task = GraduationTask.find_by(id: graduation_task_id)
     return if task.blank?
+    course = task.course
+    return if course.blank?
 
     attrs = %i[
       user_id trigger_user_id container_id container_type parent_container_id parent_container_type
@@ -18,7 +20,7 @@ class GraduationTaskPublishNotifyJob < ApplicationJob
       viewed: 0, tiding_type: 'GraduationTask'
     }
     Tiding.bulk_insert(*attrs) do |worker|
-      task.course.course_members.pluck(:user_id).uniq.find_each do |user_id|
+      course.course_members.pluck(:user_id).uniq.find_each do |user_id|
         worker.add same_attrs.merge(user_id: user_id)
       end
     end
diff --git a/app/jobs/submit_graduation_work_notify_job.rb b/app/jobs/submit_graduation_work_notify_job.rb
index 17cfc21d2..d4bb21cc4 100644
--- a/app/jobs/submit_graduation_work_notify_job.rb
+++ b/app/jobs/submit_graduation_work_notify_job.rb
@@ -19,11 +19,12 @@ class SubmitGraduationWorkNotifyJob < ApplicationJob
         next unless User.exists?(id: user_id)
 
         work = task.graduation_works.find_by(user_id: user_id)
-        next if work.blank?
+        member = course.students.find_by(user_id: user_id)
+        next if work.blank? || member.blank?
 
         attrs = same_attrs.merge(trigger_user_id: user_id, container_id: work.id)
 
-        course.course_member(user_id).member_teachers.find_each do |teacher|
+        member.member_teachers.find_each do |teacher|
           worker.add attrs.merge(user_id: teacher.user_id)
         end
       end
diff --git a/app/jobs/submit_student_work_notify_job.rb b/app/jobs/submit_student_work_notify_job.rb
index acb7873ac..c4dff264c 100644
--- a/app/jobs/submit_student_work_notify_job.rb
+++ b/app/jobs/submit_student_work_notify_job.rb
@@ -19,11 +19,12 @@ class SubmitStudentWorkNotifyJob < ApplicationJob
         next unless User.exists?(id: user_id)
 
         work = homework.student_works.find_by(user_id: user_id)
-        next if work.blank?
+        member = course.students.find_by(user_id: user_id)
+        next if work.blank? || member.blank?
 
         attrs = same_attrs.merge(trigger_user_id: user_id, container_id: work.id)
 
-        course.course_member(user_id).member_teachers.find_each do |teacher|
+        member.member_teachers.find_each do |teacher|
           worker.add attrs.merge(user_id: teacher.user_id)
         end
       end
diff --git a/app/models/course_member.rb b/app/models/course_member.rb
index d9995d463..7db681e67 100644
--- a/app/models/course_member.rb
+++ b/app/models/course_member.rb
@@ -146,11 +146,11 @@ class CourseMember < ApplicationRecord
   def member_teachers
     teacher_groups = course.teacher_course_groups
     if teacher_groups.count > 0
-      member_ids = teacher_groups.where(course_group_id: self.try(:course_group_id)).pluck(:course_member_id)
+      member_ids = teacher_groups.where(course_group_id: self.try(:course_group_id)).pluck(:course_member_id).compact
 
-      none_group_teachers = teacher_groups.pluck(:course_member_id).size > 0 ? teacher_groups.pluck(:course_member_id).join(',') : -1
-      teachers = course.teachers.where("members.id not in (#{none_group_teachers}) or
-                                            members.id in (#{member_ids.size > 0 ? member_ids.join(',') : -1})")
+      none_group_teachers = teacher_groups.pluck(:course_member_id).size > 0 ? teacher_groups.pluck(:course_member_id).compact.join(',') : -1
+      teachers = course.teachers.where("course_members.id not in (#{none_group_teachers}) or
+                                            course_members.id in (#{member_ids.size > 0 ? member_ids.join(',') : -1})")
     else
       teachers = course.teachers
     end