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', 'f3535ff6c2fc2dfe8d86f0942884e48b', '216.73.216.251', '1752522639', '1752522639', '/index.php/language/de/cat/c30_Countries.html/page/6')

[XT SQL Error]