1366 - Incorrect integer value: '' for column `DBchUcr8hevu`.`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', '30ug85kdn8vkd064lle7rij9h3', '216.73.216.131', '1771009991', '1771009991', '/shop/index.php/cat/c2_Probenhaehne.html/XTCsid/9b893c57c158503b193cd084bb3ab337')

[XT SQL Error]