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', 'or5sva65f09rs16ut9b3l0peu7', '216.73.216.217', '1751518356', '1751518356', '/product_info.php?info=p502_804954-Elektrische-Getreidemuehle--geeignet-fuer-Lebensmittel.html')

[XT SQL Error]