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', '8n5cpku8f78q5hbvp9mmik3lu0', '18.97.14.82', '1747097328', '1747097328', '/xtshop/account.php')

[XT SQL Error]