Field value hard to access after query

[wxdqz]

Hi

For some reason I can't get "first_name" to echo to the browser. "username" and "password" echo fine.

I need to pass it to the next page in a query_string. I can only get it to show up if I do a lot of formatting which I don't need or want to do.
..........

$sql = "select first_name, username, password from users where username='$username' and password='$password'";

$result = mysql_query($sql);
$num = mysql_numrows($result);

if ($num == 1) {
echo $first_name;
}
.........

Thanks!

Richard