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', 'p86gumhjbjb23v2ib7g6d2enl0', '3.236.59.63', '1594786527', '1594786527', '/')

[XT SQL Error]