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', '7c6e736c55b87a04ec222c5f0fbd098e', '216.73.216.191', '1758146929', '1758146929', '/index.php/language/de/refID/1')

[XT SQL Error]