Refactoring: Move functionality of BedHeightAccess into BedHeightFacet for now. Idea is that Artifact and Access are lightweight. Access access the 'data' ('parameterization') attached to artifact, not the data delivered by means of artifact and its parameterization.

select.abflusstafel = \
    SELECT ABFLUSSTAFEL_NR, \
           ABFLUSSTAFEL_BEZ, \
           GUELTIG_VON, \
           GUELTIG_BIS, \
           PEGELNULLPUNKT, \
           AT.BFG_ID \
    FROM ABFLUSSTAFEL AT \
    WHERE MESSSTELLE_NR LIKE :number