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', '3377d14766c4ae1cd3b70e55d5c52103', '216.73.216.46', '1757038402', '1757038402', '/index.php/cat/c19_Reliefkarten-Digital.html?refID=2')

[XT SQL Error]