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', '1jmq1a4e7sqdhupm3fcn8lp3e1', '2600:1f28:365:80b0:7cb9:fb:26c1:e368', '1786633445', '1786633445', '/')

[XT SQL Error]