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', 's10q63esobqn9ndcqsk6m6gh77', '216.73.216.165', '1752394149', '1752394149', '/shop_content.php?coID=8&XTCsid=792dd2eece839333bab562194e3fb545')

[XT SQL Error]