1366 - Incorrect integer value: '' for column `CP_as15`.`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', 'ii3qu2tdb7eeid9vdgrgkmlo92', '3.21.206.153', '1738998694', '1738998694', '/index.php?XTCsid=8e9c41f9ih262sbjeph8l1hut4&cat=c640_Netzteile.html')

[XT SQL Error]