text: USE Uebungen;
  
  SELECT id, stueck, preis, preis*1.19 AS Bruttopreis FROM lager;
  
  SELECT stueck, COUNT(id) FROM lager GROUP BY stueck;
  
  SELECT stueck, COUNT(id) FROM lager WHERE stueck<10 GROUP BY stueck;
  
  SELECT stueck, COUNT(id) FROM lager WHERE stueck<10 GROUP BY stueck ORDER BY stueck DESC;
   