anchor.diff:  foldr(_DB, _Fun, Acc, {_, End, Start, _}, _MaxNum) when Start < End -> Acc;
   foldr(DB, Fun, Acc, {El}, _MaxNum) ->
       case mnesia:transaction(fun()-> mnesia:read(DB, El) end) of
  -      {atom, []} ->
  +      {atomic, []} ->
               Acc;
  -      {atom, [_Entry]} ->
  +      {atomic, [_Entry]} ->
               Fun(El, Acc)
       end;
   foldr(DB, Fun, Acc, all, MaxNum) ->
  
positive.code: 
  -export([traverse_table_and_show/1]).
  
  traverse_table_and_show(Table_name)->
    Iterator =  fun(Rec,_)->
      io:format("~p~n",[Rec]),
      []
    end,
    case mnesia:is_transaction() of
  
negative.code:                     false ->
                          element(1, Entry) =/= '$end_of_table'
                  end),
      {atomic, _} = mnesia:transaction(fun() -> mnesia:write({DBName, element(1, Entry), Entry}) end),
      DBName.
  
  %% @doc Returns the entry that corresponds to Key or {} if no such tuple exists.
  