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', '3rikp54rs4eioorkjhp8r3c8c2', '216.73.216.165', '1752301425', '1752301425', '/index.php?cat=c2_Decoration.html&XTCsid=07630e5b15e9155d8246af3ee660ca0e')

[XT SQL Error]