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', 'f8594f7cd59ebe09abc177f9d85ffcb0', '3.135.219.166', '1714072241', '1714072241', '/popup_content.php/coID/1')

[XT SQL Error]