1366 - Incorrect integer value: '' for column `hbl_shop`.`whos_online`.`customer_id` at row 1

insert into whos_online (customer_id, full_name, session_id, ip_address, time_entry, time_last_click, last_page_url) values ('', 'Guest', 'j9t2evk3e11j6lknudmpq55d07', '216.73.216.47', '1757817997', '1757817997', '/product_info.php?info=p32_800529-Ruebenmuehle--Standgeraet.html')

[XT SQL Error]