[RESOLU] syntaxe select/mysql_num_rows

$url = "http://www.****.fr".$_SERVER['REQUEST_URI'];

          $res = mysql_query("SELECT COUNT(*) FROM sitemapurls WHERE url='$url'");
               $res2 = mysql_num_rows($res);
                  //echo $res.'<br/>'.$res2.'<br/>';
               if( $res2 > 0 ){
                    //l'url existe, on ne fait rien...
                    echo "url déja dans la base";}
               else {
                   //L'url n'existe pas, on l'ajoute
                         $sql2 = "INSERT INTO sitemapurls (url) VALUES ('$url')";
                             mysql_query($sql2) or die("MySQL query error2");
                         echo "url inséré dans la base";
                         }