title: mysql_insert_id with update
body: <p>After executing the query below I use the PHP function <code>mysql_insert_id()</code> and it always gives me 0.</p>
  
  <pre><code>UPDATE 
      tbl_training_types 
  SET 
      fld_serial = $serial_no, 
      fld_name = $training_name, 
      fld_description = $training_description 
  WHERE 
      fld_id = $id
  </code></pre>