1366 - Incorrect integer value: '' for column `abtecsho_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', '3rnns4t8496189mreum64a67b5', '216.73.216.6', '1752290322', '1752290322', '/shop_content.php/coID/14/content/Muster-Widerrufsformular')

[XT SQL Error]