1366 - Incorrect integer value: '' for column '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', '420c9e53d01da89b63470818fa404678', '18.226.98.89', '1722049429', '1722049429', '/product_info.php/info/p6_Sommerhonig-Linde.html')

[XT SQL Error]