title: Rails: Update model attribute without invoking callbacks
body: <p>I have a User model that has a :credits attribute.   I want a simple button that will add 5 to  the user's credits, through a route called "add" so that /users/3/add would add 5 to the credits of user id = 3.</p>
  
  <pre><code>def add
      @user = User.find(params[:id])
      @user.credits += 5
      redirect_to root_path
  end
  </code></pre>
  
  <p>That is the relevant part of my controller.  The problem is, I dont want to call @user.save because I have a before_save callback that re-encrypts the user's password based on the current UTC time.   I just want to simply add 5 to the attribute and avoid the callback, I never thought such a simple thing could be so hard.</p>
  
  <p>EDIT:</p>
  
  <p>I changed the callback to :before_create,
  here is my new controller code (relevant part):</p>
  
  <pre><code>  def add
      @user = User.find(params[:id])
      @user.add_credits(5)
      @user.save
      flash[:success] = "Credits added!"
      redirect_to root_path
    end
  </code></pre>
  
  <p>and here is my code in the model:</p>
  
  <pre><code> def add_credits(num)
      self.credits = num
   end
  </code></pre>
  
  <p>EDIT 2:</p>
  
  <p>Ok it was a validation problem that made the changes in "EDIT" not work, but I'd still love an answer to the original question of updating without callbacks!</p>