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', '69l628dm8s9v6du6oa8v40f6i1', '216.73.216.82', '1752530880', '1752530880', '/product_info.php?info=p10_3-packs-Blow-outs.html&XTCsid=4299a8bbf7f56cb5a06703b866244eb3')

[XT SQL Error]