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', 'q1k8mfmajmr6l6s4bb85rv9ht3', '3.15.140.16', '1738994178', '1738994178', '/index.php?XTCsid=3ea3bnp0vmbqarg8bfequsbfv5&cat=c180_Hilti-Werkzeug-Akku.html')

[XT SQL Error]