anchor.diff:    ReadOptions = [{snapshot, Snapshot}],
     IncludeDoc = proplists:get_value(include_doc, Opts, false),
     Opts2 = [{read_options, ReadOptions} | Opts],
  -  
  +
     WrapperFun = fun(_Key, BinDocInfo, Acc) ->
       DocInfo = binary_to_term(BinDocInfo),
       RevId = maps:get(current_rev, DocInfo),
  
positive.code: clean_db(Name, DbId, #{db := Db}) ->
    DbKey = << 0, 0, 0, 100, (barrel_lib:to_binary(Name))/binary >>,
    ok = erocksdb:delete(Db, DbKey, [{sync, true}]),
    spawn(fun() -> clean_db1(Db, DbId) end),
    ok.
  
  all_dbs(#{db := Db}) ->
    Fun = fun
  
negative.code:               get_doc_rev(Db, DbId, DocId, RevId, ReadOptions);
              false -> {ok, nil}
            end,
  
      Fun(DocId, DocInfo, Doc, Acc)
    end,
  
    try fold_prefix(Db, Prefix, WrapperFun, AccIn, Opts2)
    after erocksdb:release_snapshot(Snapshot)
    end.
  