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', 'k84h2p2sr92g11mpkn8u7i4ae0', '216.73.216.180', '1767085950', '1767085950', '/shop_content.php?XTCsid=0045c82a20eb26c176bef1fc0ba16df3&coID=7')

[XT SQL Error]