title: Trap key violation
body: <p>hi i'm trying to do some exception handling and intercept a repeated field value (key violation) error. From my searching for a solution ive seen many suggestions to trap all errors using</p>
  
  <pre><code>try
  (enter code)
  except on E: EDatabaseError do
  showmessage (Error message);
  end; 
  </code></pre>
  
  <p>but I'd like to respond specifically to a key violation, it uses an access table using ADO.</p>