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', 'd7301fc5e52ca3f5e3d9a7a741d4c3d0', '18.119.131.72', '1713897635', '1713897635', '/redirect.php?action=product&id=8')

[XT SQL Error]