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', 'gm3hfg37n3ickhbhi43sc4p351', '18.221.145.198', '1738998008', '1738998008', '/index.php?XTCsid=nj57khd41hu8ciniagj0kmvlc3&cat=c1142_Aufnahmeger--t-Akku.html')

[XT SQL Error]