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', 'b2pf1vj6h3stml872jc242e7q5', '18.118.99.234', '1746871514', '1746871514', '/xtshop/product_info.php?info=p475_.html')

[XT SQL Error]