class UpdateUserActivitiesUpdateAt < ActiveRecord::Migration
  def up
    count = UserActivity.all.count / 30 + 2
    transaction do
      for i in 1 ... count do i
      UserActivity.page(i).per(30).each do |activity|
        activity.updated_at = activity.created_at
        activity.save
      end
      end
    end
  end

  def down
  end
end