anchor.diff:  
   % for tester:
   -export([get_db_feeder/3, get_db_feeder/4]).
  -%% -export([fill_ring_feeder/3]).
  +-export([fill_ring_feeder/3]).
   -export([feeder_fix_rangen/2]).
   
   -define(ReplicationFactor, 4).
  
positive.code: % Helper functions
  %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  
  % not ready yet:
  %% -spec fill_ring_feeder(random, 1..1000, [db_parameter()])
  %%         -> {db_type(), pos_integer(), [db_parameter()]}.
  %% fill_ring_feeder(Type, DBSize0, Params) ->
  %%     Params1 =
  %%         case proplists:get_value(distribution, Params, uniform) of
  %%             {non_uniform, RanGen} = EDist0 ->
  %%                 DBSize = erlang:min(DBSize0, random_bias:numbers_left(RanGen)),
  %%                 [{distribution, feeder_fix_rangen(EDist0, DBSize)} |
  %%                      proplists:delete(fdistribution, Params)];
  %%             _ ->
  %%                 DBSize = DBSize0,
  %%                 Params
  %%         end,
  %%     {Type, DBSize, Params1}.
  
  % @doc  DBSize=Number of Data Entities in DB (without replicas)
  -spec fill_ring(db_type(), pos_integer(), [db_parameter()]) -> db_status().
  
negative.code:         wiki -> fill_wiki(Params, "barwiki-latest-pages-meta-current.db")
      end.
  
  -spec fill_random_feeder({1..1000, 1..1000}, [db_parameter()])
          -> {pos_integer(), [db_parameter()]}.
  fill_random_feeder(Sizes0, Params0) ->
      {random, DBSize, Params} = fill_ring_feeder(random, Sizes0, Params0),
      {DBSize, Params}.
  
  -spec fill_random(DBSize::pos_integer(), [db_parameter()]) -> db_status().
  fill_random(DBSize, Params) ->    
  