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', 'q05ungfp4jod935c0q92eghft1', '216.73.216.70', '1752612765', '1752612765', '/product_info.php?info=p11_Fan-for-decorations.html&XTCsid=33509f1bee4ee2cbb673a74e5faae0d4')

[XT SQL Error]