1366 - Incorrect integer value: '' for column `argus_xtc`.`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', 'vkvg3mti9g7nu8j2hj851vh0k6', '18.215.161.19', '1560711365', '1560711365', '/shop/product_info.php?info=p15_1-3--Vari-Focal-Objektiv--3-5-9-mm-Brennweite.html')

[XT SQL Error]