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', 'tri0c1nej9fulet4m5ghdc2101', '3.15.20.178', '1739000979', '1739000979', '/index.php?XTCsid=f57tq837n8rooemhginpeliql7&cat=c825_Modellbau-Akkus.html')

[XT SQL Error]