1366 - Incorrect integer value: '' for column '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', '5tc0fieq4it6e8ik02b2c85891', '216.73.216.110', '1752060993', '1752060993', '/index.php?cat=c13_Accessoires.html&XTCsid=a63f52844b6e675f480eaf86612536c2')

[XT SQL Error]