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', 'inupdme8u337rc7vaqrvr54b47', '3.15.205.161', '1738997471', '1738997471', '/index.php?XTCsid=8e9c41f9ih262sbjeph8l1hut4&cat=c1144_Cyklop-Werkzeug-Akku.html')

[XT SQL Error]