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', 'ije9e4qo4erheluoj7h9cds3t5', '54.224.85.115', '1529852452', '1529852452', '/shop/create_account.php')

[XT SQL Error]