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', 'm3halcci993ghtb3218i955nd1', '216.73.216.47', '1758094932', '1758094932', '/product_info.php?info=p634_802004-Deckel-fuer-160-Liter-Elektro-Futterdaempfer.html')

[XT SQL Error]