How to edit unique field value in mysql database? if I edit it in phpmyadmin i get what i need, but if i do this from .php by form my field doesn't edites( Whats wrong ?

here is sql code 

```
$result = mysql_query ("UPDATE client SET Code='$Code', FirstName='$FirstName', LastName='$LastName', DateBirth='$DateBirth', Other='$Other' WHERE Code=$Code");

```