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', 's10e1kvv20inulsg7hjpbmlai4', '18.234.88.196', '1558466957', '1558466957', '/lkw_plane_tasche_lkw_plane/index.php/cat/c10_30-25-8.html')

[XT SQL Error]