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', '5p4ov37143q7sdcajp10p0c4m3', '3.84.182.112', '1555937780', '1555937780', '/lkw_plane_tasche_lkw_plane/product_info.php/info/p2_28-20-08.html')

[XT SQL Error]