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', 'o8b00cp20uni4ouucqnmrhk9e3', '18.234.255.5', '1607110957', '1607110957', '/')

[XT SQL Error]