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', '4hicatjmdp8sqf7hkft7kpifd7', '3.133.112.201', '1738998951', '1738998951', '/index.php?XTCsid=rkdf8qfiujodbcb5st13ohfmn6&cat=c1140_Zahlungsterminal-Akkus.html')

[XT SQL Error]