Migration to add timestamps easily to a bunch of tables

20171004211734_add_timestamps_everywhere.rb

class AddTimestampsEverywhere < ActiveRecord::Migration[5.1]
  def change
    now = Time.current

    %i[
      candidates
      evaluations
      interviewers
      questions
      responses
      stages
      workflows
    ].each do |table|
      change_table table do |t|
        t.timestamps null: true
      end

      klass = Class.new(ActiveRecord::Base) do
        self.table_name = table
      end

      klass.update_all(created_at: now, updated_at: now)

      change_column_null(table, :created_at, false)
      change_column_null(table, :updated_at, false)
    end
  end
end