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', 'i12b09rl8rp6g0a89bdi5m9p26', '216.73.216.72', '1787258215', '1787258215', '/index.php?XTCsid=80c3e9fc87b53cb0d288d19ef4e9b63c&cat=c6_Foodstuffs.html')

[XT SQL Error]