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', 'c2m07ldsnon3cf7fa2vrg2a6u0', '216.73.216.180', '1766178273', '1766178273', '/index.php?XTCsid=c5d9d9a5780af7d5707e3b2046ece3fe&cat=c5_Crockery.html')

[XT SQL Error]