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', 'ljck7nr5521rk2q14lq07mf775', '216.73.216.167', '1762619128', '1762619128', '/product_info.php?XTCsid=a0c8d0b3d08cb472c84559a313755d47&info=p9_Paper-Lantern.html')

[XT SQL Error]