public function getAllProductsPagination($page, $perPage){
        $firstLink = ($page - 1) * $perPage; 
        $sql = self::$connection->prepare("SELECT * FROM `products` LIMIT $firstLink, $perPage");
        $sql->execute();
        $items = array();
        $items = $sql->get_result()->fetch_all(MYSQLI_ASSOC);
        return $items;
    }