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', 'q3jgkd5007t7cutkf7q2j2ge75', '216.73.216.147', '1751745719', '1751745719', '/product_info.php?info=p10_3-packs-Blow-outs.html&XTCsid=0308d34f52db367f9a7068f51bec2a23')

[XT SQL Error]