core/db/migrate/20140423100114_clean_enrollments_join_models.rb
class CleanEnrollmentsJoinModels < ActiveRecord::Migration[4.2]
def change
drop_table :gaku_class_group_enrollments
drop_table :gaku_class_group_course_enrollments
drop_table :gaku_course_enrollments
drop_table :gaku_extracurricular_activity_enrollments
end
end