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', '53d0283f338649473ec64095548e472d', '44.210.240.31', '1711701883', '1711701883', '/redirect.php?action=product&id=30')

[XT SQL Error]