public static function resolve($id)
    {
        global $PPHP;

        if (array_key_exists($id, self::$_resolved)) {
            return self::$_resolved[$id];
        };

        $db = $PPHP['db'];
        if ($user = $db->selectSingleArray("SELECT * FROM users WHERE id=?", array($id))) {
            return self::$_resolved[$id] = $user;
        };
        return false;
    }