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', '4rc6v9hv9bhv39cn4r0sj1q2c7', '3.12.154.243', '1738997460', '1738997460', '/index.php?XTCsid=nmu1l7bj1113ksvu525rsptc72&cat=c672_Tablet-PC---E-Book-Akku.html')

[XT SQL Error]