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', 'o79col5t1dpmp8rb0qlionooa0', '216.73.216.9', '1758202796', '1758202796', '/product_info.php?XTCsid=33509f1bee4ee2cbb673a74e5faae0d4&info=p7_Garland-13-feet.html')

[XT SQL Error]