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', 's4fdh7e9v423v4vbm0s99rgrj4', '216.73.216.9', '1758150297', '1758150297', '/product_info.php?XTCsid=a0c8d0b3d08cb472c84559a313755d47&info=p6_100-Paper-Plates.html')

[XT SQL Error]