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', '0a8mh7h6f5meo56sgca1s9be30', '216.73.216.197', '1751513272', '1751513272', '/shop_content.php?coID=2&XTCsid=a0c8d0b3d08cb472c84559a313755d47')

[XT SQL Error]