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', 'niq65giccve4bd672au5evbeq4', '18.232.171.18', '1566446040', '1566446040', '/product_info.php?info=p103948_A-C-M-E-55187-Zug-Nightjet-EN-295-40295-Munchen---Milano-Roma-H0.html')

[XT SQL Error]