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', '6cefd9f09dac254e15decc3f037b0ed8', '3.15.219.64', '1713416445', '1713416445', '/index.php')

[XT SQL Error]