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', '2p17slgftcbf03s9emoguvn4u6', '216.73.217.62', '1783165831', '1783165831', '/product_info.php?XTCsid=ee199fdb171da456469b100b0e4b3f11&info=p18_Fun-Hat.html')

[XT SQL Error]