Motto changing site [EACH CMS]

[Mininova]

ok i test how long i need:

<?php
$motto = htmlspecialchars($_POST['motto']);
if(isset($motto){
mysql_query("UPDATE users SET motto = '".$motto."' WHERE id = '".$user['id']."'");
}
?>
<form action="#" method="POST">
<input type="text" value="<?php echo $user['motto'] ?>" name="motto">
<input type="submit" value="Change">

ok i need without any help (Written from my Brain) 1 Minute ^^ (I must answer an Friend in Steam xD)