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', '4e44c2e4b48efd7a5b0788add111b806', '3.144.187.103', '1713882625', '1713882625', '/redirect.php?action=product&id=17')

[XT SQL Error]