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', 'croi3g6vll2ev2uh5q34h55gs1', '216.73.217.0', '1790125975', '1790125975', '/product_info.php?XTCsid=69a1e06b1d537d651878c63fe4ee3fec&info=p12_33-feet-crape-paper.html')

[XT SQL Error]