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', '3dm9594r0nf0o0jtm44ktg5nl5', '216.73.216.99', '1761889697', '1761889697', '/product_info.php?XTCsid=38f09672db884903e3803adf9d076819&info=p10_3-packs-Blow-outs.html')

[XT SQL Error]