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', '6vqknbe59flu3uroks33aqp7k5', '216.73.216.165', '1752301917', '1752301917', '/product_info.php?info=p10_3-packs-Blow-outs.html&XTCsid=7c604026da355cfd6a094c68b431572d')

[XT SQL Error]