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', 'lijlhhni0tn4mrmpcssr7v7fs2', '2600:1f28:365:80b0:a70:aa3d:556d:966d', '1778698584', '1778698584', '/')

[XT SQL Error]