SELECT Region, count(DISTINCT Cru) FROM Vin GROUP BY Region;
SELECT Nom, NumVitic, count(DISTINCT Cru) FROM Viticulteur NATURAL JOIN Vin GROUP BY Nom, NumVitic;
SELECT NumBuveur, Nom, AVG(Qtte) FROM Buveur NATURAL JOIN Commande WHERE Ville = 'PARIS' GROUP BY NumBuveur, Nom;
SELECT Nom, Count(NumCom) FROM Commande NATURAL JOIN Buveur GROUP BY Nom;
SELECT Nom, COUNT(Qtte) FROM Buveur NATURAL JOIN Commande GROUP BY Nom HAVING AVG(Qtte) >= 12;