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', 'o4mum9jsufu9mr0ld0fe9j9hd3', '216.73.216.130', '1761112717', '1761112717', '/index.php?XTCsid=15cbbc13723f7bc63afaf1294f637517&cat=c8_Disposable-tableware.html')

[XT SQL Error]