oh dear-

pardon my ignorance but,
class user{
private $user_id;
private $user_name;
public function __construct($user_id) {
$this -> user_id=$user_id;
$this -> user_name = $result['username'];

what is '$this ->'

Oh, and C++ isn't fucking OO either, it's just badly duct-taped-together half-OO shit.