1366 - Incorrect integer value: '' for column `agentur`.`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', 'dre12annugcp4hf9ts6ug51t47', '18.207.106.142', '1600706524', '1600706524', '/index.php?cat=c36_Grand-Re-Opening-von-Cartier-Boutique-Hamburg.html&XTCsid=2d4qg7ftupcpr3opjmmv969b12')

[XT SQL Error]