'.$link_content.''; return $out; } ?>1366 - Incorrect integer value: '' for column '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', '2fe186b20f5f568a291fe386679f2b63', '3.81.89.248', '1638419409', '1638419409', '/rubikmazeshop/')

[XT SQL Error]