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', 'pub3e3od9dsa8j8m5sg1ml60j3', '18.234.88.196', '1558465365', '1558465365', '/lkw_plane_tasche_lkw_plane/index.php/cat/c9_30-38-10.html')

[XT SQL Error]