Merge pull request #7 from taikano/patch-1

corrected SQL statement

documents/musterloesung-db-klausur-b/d3c.sql

@@ -1,3 +1,4 @@
-SELECT name FROM Berater
-    JOIN Kunden, Kunden2Berater, Berater 
-    WHERE Kunden.name = "Müller"
+SELECT name FROM Berater b
+    JOIN Kunden2Berater  kb ON kb.berater_id = b.berater_id
+    JOIN Kunden k ON k.kunden_id = kb.kunden_id
+    WHERE k.name = "Müller"