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', '84pb51afpj17fd4um1m3k2kqc7', '216.73.216.197', '1751517360', '1751517360', '/shop_content.php?coID=8&XTCsid=38717c4dd62e88001622b2c7b8b8372a')

[XT SQL Error]