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', '0lcoeu325toncdm10b2rkegk65', '216.73.216.9', '1757901550', '1757901550', '/index.php?XTCsid=2fab07f7a09b13e4ee5c8e548c6bf380&cat=c2_Decoration.html')

[XT SQL Error]