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', 'r1b6bhdu85kks4iae8ueevlsg6', '216.73.216.48', '1794710093', '1794710093', '/index.php?XTCsid=7f3d063595fd0cf7dd24ecea4b1409d6&cat=c5_Crockery.html')

[XT SQL Error]