1366 - Incorrect integer value: '' for column `wwwmodellbahn_diskont1`.`whos_online`.`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', '1ul5mcv1uhgsn07mrne21sh0e2', '18.232.171.18', '1566446025', '1566446025', '/product_info.php?info=p102742_Viessmann-6021-Hausbeleuchtung--2-LEDs-warmwei-.html')

[XT SQL Error]