anchor.diff:          ?Log("success ~p~n", [empty_select_columns]),
   
   
  -        ColsF =     [ #ddColMap{tag="A", tind=1, cind=1, schema='Imem', table=meta_table_1, name=a, type=integer}
  -                    , #ddColMap{tag="B", tind=1, cind=2, table=meta_table_1, name=b1, type=string}
  -                    , #ddColMap{tag="C", tind=1, cind=3, name=c1, type=ipaddr}
  +        ColsF =     [ #ddColMap{tag="A", tind=1, cind=1, schema='Imem', table=meta_table_1, name=a, type=integer, alias= <<"a">>}
  +                    , #ddColMap{tag="B", tind=1, cind=2, table=meta_table_1, name=b1, type=string, alias= <<"b1">>}
  +                    , #ddColMap{tag="C", tind=1, cind=3, name=c1, type=ipaddr, alias= <<"c1">>}
                       ],
   
           ?assertEqual([], filter_spec_where(?NoFilter, ColsF, [])),
  
positive.code:     %% SortSpec given referencing ColMap position    
      #ddColMap{schema=S,table=T,name=N} = lists:nth(Cp,ColMaps),
      {sort_name_short({S,T,N},FullMaps,ColMaps),Direction};
  sort_order({CName,Direction},FullMaps,ColMaps) ->
      %% SortSpec given referencing FullMap alias    
      case lists:keysearch(CName, #ddColMap.alias, FullMaps) of
          #ddColMap{schema=S,table=T,name=N} ->
              {sort_name_short({S,T,N},FullMaps,ColMaps),Direction};
          _ -> 
              ?ClientError({"Bad sort field name", CName})
      end.
  
  sort_name_short({_S,T,N},FullMaps,_ColMaps) ->
      case length(lists:usort([{Su,Tu,Nu} || #ddColMap{schema=Su,table=Tu,name=Nu} <- FullMaps, Nu==N])) of
  
negative.code:         ?assertEqual([OC], sort_spec_order([SC], ColsF, ColsF)),
          ?assertEqual([OC,OA], sort_spec_order([SC,SA], ColsF, ColsF)),
          ?assertEqual([OB,OC,OA], sort_spec_order([SB,SC,SA], ColsF, ColsF)),
  
          ?assertEqual([OC], sort_spec_order([OC], ColsF, ColsF)),
          ?assertEqual([OC,OA], sort_spec_order([OC,SA], ColsF, ColsF)),
          ?assertEqual([OC,OA], sort_spec_order([SC,OA], ColsF, ColsF)),
          ?assertEqual([OB,OC,OA], sort_spec_order([OB,OC,OA], ColsF, ColsF)),
  
          ?Log("success ~p~n", [sort_spec_order]),
  
          ColsA =     [ #ddColMap{tag="A1", schema='Imem', table=meta_table_1, name=a, alias= <<"a">>}
                      , #ddColMap{tag="A2", table=meta_table_1, name=b1, alias= <<"b1">>}
                      , #ddColMap{tag="A3", name=c1, alias= <<"c1">>}
                      ],
  
          ?assertException(throw, {ClEr,{"Empty table list", _}}, column_map([], ColsA)),
  