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', '2ff19fe615b91378568b2dfd90e4da60', '216.73.216.121', '1751591010', '1751591010', '/index.php/cat/c19_Reliefkarten-Digital.html?refID=1')

[XT SQL Error]