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', 'tk7oeokthk9gf5gt44ivv24720', '216.73.216.99', '1761933577', '1761933577', '/product_info.php?XTCsid=1ce6d0a6925740e42ccf6986944a240a&info=p19_10-Paper-Plates.html')

[XT SQL Error]