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', '8s578htj7jjsng5g0bf5h0e5q6', '216.73.216.45', '1758214249', '1758214249', '/shop_content.php?coID=20')

[XT SQL Error]