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', 'e225f5e93cdb685926c93b6c31467727', '3.141.202.187', '1714019155', '1714019155', '/redirect.php?action=product&id=19')

[XT SQL Error]