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', 'drr2n4dm8t1a719pu1odjq9vf4', '216.73.216.130', '1760819515', '1760819515', '/product_info.php?XTCsid=d0fb6f95a363340d124d7dc76e615e44&info=p18_Fun-Hat.html')

[XT SQL Error]