CREATE PROCEDURE Statystyka
AS
SELECT SUM(f.wartosc) AS przychod,
MONTH(f.DATA) AS miesiac,
YEAR(f.DATA) AS rok,
AVG(f.wartosc) AS [srednia na klienta],
MAX(f.wartosc) AS [sprzedaz maksymalna],
MIN(f.wartosc) AS [sprzedaz minimalna]
FROM Faktura AS f GROUP BY MONTH(f.DATA), YEAR(f.DATA)
GO