1366 - Incorrect integer value: '' for column `pella-ware`.`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', '7f751ea7a1486b33495e668b048dddbe', '18.207.98.249', '1711695718', '1711695718', '/shop_content.php?language=de&coID=2')

[XT SQL Error]