title: EMPTY $dbh->get_results($query) IN WORDPRESS
body: <p>I'm executing that code in a Wordpress. The wordpress is working fine, the query in the phpmyadmin is returning results. But <code>$sets</code> is empty. 
  All the other things in wordpress is working fine. </p>
  
  <pre><code>global $wpdb; echo DB_NAME; echo DB_PASSWORD; ECHO DB_HOST;
  $dbh = new wpdb(DB_USER, DB_PASSWORD, DB_NAME, DB_HOST);
  $table = "dp";  
  $query = "SELECT DISTINCT(id_set) FROM $table WHERE id_producto = ".$idproducto;
  $sets = $dbh-&gt;get_results($query);var_dump($dbh);
  if (isset($sets)) return $sets;
  else return false;
  </code></pre>
  
  <p>Thanks in advance</p>