GROUP BY a single field, show all fields

Question

I have this table:
CREATE TABLE Prices(ServiceType VARCHAR2(30), EffectiveDate DATE, Fee NUMBER, Commission NUMBER, PRIMARY KEY(ServiceType, EffectiveDate));
I am trying to write an SQL query to get the ServiceTypes and Fees. However, I only want those with the most recent EffectiveDate.
This is what I have so far:
SELECT ServiceType, Fee, MAX(EffectiveDate) FROM Prices GROUP BY ServiceType;
But that doesn't work because GROUP BY has to be followed by all selected attributes. Does anyone know how to write that query? Thanks in advance,
Nader

Answer 1

Why dont you use a sub query liek below:
SELECT ServiceType
            , Fee
            , EffectiveDate
  FROM Prices    out
WHERE EffectiveDate = ( SELECT MAX(EffectiveDate)
                                         FROM Prices   in
                                      WHERE in.ServiceType = out.ServiceType
                                           AND in.Fee              = out.Fee 
                                  GROUP BY ServiceType
                                                  , Fee
                                    );Regards
Arun