1366 - Incorrect integer value: '' for column `hbl_shop`.`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', '60i87c7c20o88k6pn4rulmr706', '216.73.216.129', '1765800419', '1765800419', '/product_info.php?info=p70_802165-Edelstahlkanne-1-5-Liter.html')

[XT SQL Error]