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', '5asqe6mo2ccn376bd3qnohte46', '216.73.216.82', '1752529057', '1752529057', '/product_info.php?info=p10_3-packs-Blow-outs.html&XTCsid=33509f1bee4ee2cbb673a74e5faae0d4')

[XT SQL Error]