title: Cannot modify variable at before_save?
body: <p>I have the ff code in my Model:</p>
  
  <pre><code>before_save :before_save_method
  
  attr_accessor :corrective_change
  attr_accessible :corrective_change
  attr_accessible :corrective_desc
  
    private 
      def before_save_method
        if corrective_change == 0
          self.corrective_desc = corrective_desc_was
        end
      end
  </code></pre>
  
  <p>However, whatever the value of <code>corrective_change</code> is, the value of <code>self.corrective_desc</code> still update by the input value from users.</p>
  
  <p>The value of all variable are tested and I can view them in logger just fine as they should be, but the condition doesn't work.</p>
  
  <p>Can anyone point out what the problem is?</p>
  
  <p>Thank you very much.</p>