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', 'nvg6moersiq9dnnqo8d1mvvbe1', '3.84.182.112', '1555939058', '1555939058', '/lkw_plane_tasche_lkw_plane/product_info.php/info/p18_Gutschein-60-EUR.html')

[XT SQL Error]