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', 'q02hvrvhjvkecdnlbtc3gi8u93', '216.73.216.179', '1751414761', '1751414761', '/product_info.php?info=p611_800543-Ruebenmuehle--Tischgeraet-mit-Standardwalze.html')

[XT SQL Error]