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', 'v7oi36vkur1b3mue8nuvdouv10', '3.144.115.20', '1746763501', '1746763501', '/xtshop/account.php')

[XT SQL Error]