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', 'rp1u39dr7ntt1qn75tc3f5k6h4', '18.216.253.53', '1738996352', '1738996352', '/index.php?XTCsid=3ea3bnp0vmbqarg8bfequsbfv5&cat=c841_Li-ion-3-6V---3-7V-Rundzellen.html')

[XT SQL Error]