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', 'n6lmn9c2mc4pglc05a2o8ohrp4', '3.19.75.212', '1747120221', '1747120221', '/product_info.php?info=p21_800215-Schlammsieb-fuer-E-Futterdaempfer-26-Liter.html')

[XT SQL Error]