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', 'm3u2cvrksj47l1ofik63m7v8f5', '216.73.216.76', '1789128895', '1789128895', '/product_info.php?XTCsid=33509f1bee4ee2cbb673a74e5faae0d4&info=p16_Octoberfest-CD.html')

[XT SQL Error]