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', '43uou74uct63i1cd4rcl6tv3k7', '216.73.216.69', '1789743947', '1789743947', '/shop_content.php?XTCsid=67a1ee4a966bad4e2954e4e321814afb&coID=4')

[XT SQL Error]