1366 - Incorrect integer value: '' for column `CP_as15`.`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', '4a48h5fubh3t8fi60vp6kg4bv7', '18.227.134.23', '1739000789', '1739000789', '/index.php?XTCsid=u26kusssenv9nf8n7cr2rtvfn3&cat=c1142_Aufnahmeger--t-Akku.html')

[XT SQL Error]