撤销发布的试卷要删除之前做过的题目

app/controllers/exercise_controller.rb

@@ -728,6 +728,7 @@ class ExerciseController < ApplicationController
       ExerciseShixunAnswer.where(:exercise_question_id => @exercise.exercise_questions.pluck(:id)).destroy_all
       @exercise.update_attributes(:exercise_status => 1, :publish_time => nil, :end_time => nil, :unified_setting => 1)
       @exercise.exercise_group_settings.destroy_all
+      @exercise.exercise_user_questions.destroy_all
       @exercise.course_acts.destroy_all
       @exercise.tidings.destroy_all
       create_exercises_list @exercise