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', 'g23pqtso9d9gqfli2nudhlpuo2', '3.147.28.73', '1739000960', '1739000960', '/index.php?XTCsid=o64jeukdqdg9btq7j80htrr7d3&cat=c1279_Drucker.html')

[XT SQL Error]