if (!isset($group_id)) {
if (!isset($lookup) || !isNum($lookup)) fallback("index.php");
$result = dbquery("SELECT * FROM ".$db_prefix."users WHERE user_id='$lookup'");
if (dbrows($result)) { $data = dbarray($result); } else { redirect("index.php"); }
<a href='profile.php?lookup=".$data['user_id']."'>