prova con:

echo "<table width=\"100%\" border=\"1\">";

$query = "SELECT c1, c2, c3, c4, c5, c6 FROM tabella";
$req = mysql_query($query);
$res = mysql_num_rows($req);

if ($res == 0)
{ echo "<center>Sorry there is no result.</center>";}
else
{ while($row = mysql_fetch_array($richiesta))
{
extract($row);

echo "<tr>
<td>c1</td>
<td>c2</td>
<td>c3</td>
<td>c4</td>
<td>c5</td>
<td>c6</td>
</tr>";


}
}

echo "</table>";

ciao