Supporting Views
•1.  Create View PartialResult as
•     (Select E.eid, E.sal, E.did
•      From   Emp E, Dept D
•      Where  E.did=D.did
•         And   E.age < 30  and D.budget > 100K)
2.Create View Filter AS
•        Select DISTINCT P.did FROM PartialResult P.
2.Create View LimitedAvgSal as
•        (Select F.did Avg(E.Sal) as avgSal
•        From Emp E, Filter F
•        Where E.did=F.did
•        Group By F.did)