SELECT             a.*,
                   b.*
FROM   tbladressen a
       INNER JOIN tblkdmerkmale k ON
             a.AdressNr = k.KmAdressNr
WHERE  a.Gesperrt <> 'Ja'
       AND EXISTS (SELECT * FROM tblkdmerkmale k
                   WHERE k.KmAdressNr = a. AdressNr
                         AND (k.KmBez = '2014' OR k.KmBez = '2015')),
GROUP BY a.AdressNr