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', 'gbg6v5voul3d4jjruagpfom8c3', '3.142.248.196', '1739000948', '1739000948', '/index.php?XTCsid=phknodh461cpg07ie5v3k6t3b7&cat=c1023_Werkzeugakku-LED-Lampen.html')

[XT SQL Error]