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', '26i5oapvqqh05a2ctu4u6t7kj2', '3.227.2.109', '1571505524', '1571505524', '/shop/index.php?cat=c244_Computer-und-Notebooks.html')

[XT SQL Error]