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', 'd40b189631fbfa64da253dae0f61b789', '3.239.129.91', '1653328183', '1653328183', '/shop/index.php')

[XT SQL Error]