|
class DeleteNullCourseActivity < ActiveRecord::Migration
|
|
def up
|
|
count = CourseActivity.all.count / 30 + 2
|
|
transaction do
|
|
for i in 1 ... count do i
|
|
CourseActivity.page(i).per(30).each do |activity|
|
|
unless activity.course_act
|
|
activity.destroy
|
|
end
|
|
end
|
|
end
|
|
end
|
|
end
|
|
|
|
def down
|
|
end
|
|
end
|