title: MAX and CONVERT with mysql
body: <p>i have made this:</p>
  
  <pre><code>SELECT MAX(CONVERT((numeroerba), INTEGER)) AS tot FROM cert_erba
  </code></pre>
  
  <p>I am trying to extract and convert a number from varchar to int but do not understand what is wrong.</p>
  
  <p>No data return.</p>