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', 'gdp72tsigtu5548p8n1ui8anv5', '216.73.216.180', '1767267888', '1767267888', '/index.php?XTCsid=679e5364f8ebcbd98062f6d07b727e6d&cat=c13_Accessoires.html')

[XT SQL Error]