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', 'llkhuk5uc6oj3mni42q4c3s0s6', '216.73.216.118', '1761633523', '1761633523', '/index.php?XTCsid=33509f1bee4ee2cbb673a74e5faae0d4&cat=c12_Music.html')

[XT SQL Error]