1366 - Incorrect integer value: '' for column `mapshopatlogis`.`whos_online`.`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', '152fdd09cd7b61bd26ebb88ad5e0ce50', '216.73.216.35', '1751511960', '1751511960', '/index.php/language/en/refID/1')

[XT SQL Error]