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', 'qgedoigg8jbic2g7dcrkm2kej5', '216.73.216.147', '1751681724', '1751681724', '/shop_content.php?coID=4&XTCsid=fba53dc6b549a2b9cad4403a2504e4ed')

[XT SQL Error]