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', '5b3q96f5q0u4i5bovbcgulqu84', '216.73.217.78', '1791260273', '1791260273', '/product_info.php?XTCsid=81fba26e1f006e30d12d9ee4d58a4030&info=p9_Paper-Lantern.html')

[XT SQL Error]