1366 - Incorrect integer value: '' for column `hbl_shop`.`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', 'bg7v4eudj3q0vkg6j0ls94o0c5', '3.14.7.99', '1746789734', '1746789734', '/product_info.php?info=p639_806408-Heizstab-fuer-Edelstahl-Bruehkessel--3-kW.html')

[XT SQL Error]