CREATE PROCEDURE CalcPvIncome
 ( BeginDate date,
   EndDate   date,
   KwPrice   decimal (2,2) )

RETURNS ( Total_PV_Production decimal (9,2),
          Total_Income decimal (9,2) )
AS
BEGIN

   FOR SELECT SUM(ENERGY/1000), SUM((ENERGY/1000) * :KwPrice)
       FROM PVPROD
       WHERE proddate >= :BeginDate AND proddate <= :Enddate
       INTO :Total_PV_Production , :Total_Income
       DO

       BEGIN
        SUSPEND ;
       END
END

SELECT
   SUM(ENERGY/1000) AS Total_PV_Production,
   sum((ENERGY/1000)*0.55) as Total_Income
FROM
   PVPROD
where
   proddate >= '12.06.2012' and  proddate <= '12.07.2012'