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', '2r69setb51ub1js8bdpnio3po4', '216.73.216.89', '1766497759', '1766497759', '/index.php?cat=c18_Ersatzteile.html')

[XT SQL Error]