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', '5ouu6bdkb4iqj7uavo3k2r1im2', '3.234.143.26', '1600947545', '1600947545', '/')

[XT SQL Error]