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', 'rgb3fol8auem46gktfonnfms64', '3.147.73.110', '1738997821', '1738997821', '/index.php?XTCsid=c8tsstf8ajiodlgrn3rqsr62b1&cat=c599_Hitachi-Werkzeug-Akku.html')

[XT SQL Error]