1366 - Incorrect integer value: '' for column `hollen`.`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, http_referer) values ('', 'Guest', '1ob4s2floab40s9vki3ul8ku45', '3.235.105.97', '1601517569', '1601517569', '/Sitemap:_:8.html', 'Keiner/None')

[XT SQL Error]