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', 'snuktmk90q1lbm6hi5m5re2fr4', '3.148.179.141', '1746958910', '1746958910', '/xtshop/product_info.php?info=p990_.html')

[XT SQL Error]