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', 'km9hha01a0iak62e4iopi7uo55', '216.73.216.128', '1771479768', '1771479768', '/product_info.php?info=p661_100-Liter-E-Daempfer-mit-Transportschaden.html')

[XT SQL Error]