毕设创建多个分班的问题

db/migrate/20200102030946_modify_course_group_for_courses.rb

@@ -1,6 +1,6 @@
 class ModifyCourseGroupForCourses < ActiveRecord::Migration[5.2]
   def change
-    groups = CourseGroup.where(course_id:3128).order("created_at desc").group(:name)
+    groups = CourseGroup.where(course_id:3429).order("created_at desc").group(:name)
     ActiveRecord::Base.transaction do
       groups.each do |g|
         CourseGroup.where(name: g.name).where.not(id: g.id).each do |cg|