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', 'f1369a46a3737cf3257650da359e1aeb', '34.239.151.124', '1718723649', '1718723649', '/shopping_cart.php')

[XT SQL Error]