|
class DeleteNoneCourseHomework < ActiveRecord::Migration
|
|
def up
|
|
count = HomeworkCommon.all.count / 30 + 2
|
|
transaction do
|
|
for i in 1 ... count do i
|
|
HomeworkCommon.page(i).per(30).each do |h|
|
|
if h.course_id.nil? || h.course.nil?
|
|
h.destroy
|
|
end
|
|
end
|
|
end
|
|
end
|
|
end
|
|
|
|
def down
|
|
end
|
|
end
|