1366 - Incorrect integer value: '' for column `meersalz_2017`.`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', 'tcfh088anpppqnblnf3nntv4v1', '3.236.98.25', '1593689741', '1593689741', '/shop_content.php?coID=1')

[XT SQL Error]