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', 'nqng5qlmllevigiv0c5t496ip1', '3.21.241.201', '1738998161', '1738998161', '/index.php?XTCsid=8e9c41f9ih262sbjeph8l1hut4&cat=c1194_Makita-4-8Volt-Akku.html')

[XT SQL Error]