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', 'h4qd874n8t79gmq9hf815he9j7', '216.73.216.28', '1765289319', '1765289319', '/index.php?XTCsid=c63b24e231384cad64f954428cedcfc2&cat=c6_Foodstuffs.html')

[XT SQL Error]