title: Rails: Check which method initiated save inside :before_save
body: <p>I want to run a method that tracks changes to a records's attributes inside the CRUD, but only when they're saved with the Update action. I have this inside the model now:</p>
  
  <pre><code>before_save :check_changed
  def check_changed
    puts "Period Contributions Changed? : #{period_contributions_changed?}"
    puts "Total Contributions Changed? : #{total_contributions_changed?}"
    puts "Period Expenditures Changed? : #{period_expenditures_changed?}"
    puts "Total Expenditures Changed? : #{total_expenditures_changed?}"
  end
  </code></pre>
  
  <p>But this runs on the creation of new records as well. Is there a test I can perform inside the check_changed method to determine whether a record was created or updated? Thanks</p>