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', 'aiop51m6mr5g4ii95cn2hvknf3', '18.216.7.205', '1746765099', '1746765099', '/xtshop/index.php?cat=c28_.html')

[XT SQL Error]