ID fra liste, der ikke er i en tabel

Ville dette virke?

SELECT
   listOfIds.id
FROM
    (      SELECT 1 AS id
     UNION SELECT 2
     UNION SELECT 3
     UNION SELECT 4
     UNION SELECT 5
     UNION SELECT 6) listOfIds
LEFT OUTER JOIN staff
ON listOfIds.id = staff.id
WHERE staff.id IS NULL

Prøv dette eksempel i SQL Fiddle .