codeocean/db/migrate/20200506093054_add_deadline_to_exercises.rb

class AddDeadlineToExercises < ActiveRecord::Migration[5.2]
  def change
    add_column :exercises, :submission_deadline, :datetime, null: true, default: nil
    add_column :exercises, :late_submission_deadline, :datetime, null: true, default: nil
  end
end