prepare("SELECT SUM(quantity) FROM cart WHERE user_id = ?"); $stmt->execute([$_SESSION['user_id']]); $cart_item_count = $stmt->fetchColumn(); } else { $stmt = db()->prepare("SELECT SUM(quantity) FROM cart WHERE session_id = ?"); $stmt->execute([session_id()]); $cart_item_count = $stmt->fetchColumn(); } $cart_item_count = $cart_item_count ?: 0; ?>