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', '8qebh1s9ec7tippagbkgl0bo82', '216.73.216.82', '1752526530', '1752526530', '/products_new.php?XTCsid=d0fb6f95a363340d124d7dc76e615e44')

[XT SQL Error]