anchor.diff:      %% Run a Map/Reduce operation using reduce_identity to get a list
       %% of BKeys.
       Input = {index, Bucket, Index, StartKey, EndKey},
  -    IdentityQuery = [{reduce, {modfun, riak_kv_mapreduce, reduce_identity}, none, true}],
  +    IdentityQuery = [{reduce,
  +                      {modfun, riak_kv_mapreduce, reduce_identity},
  +                      [{reduce_phase_only_1, true}],
  +                      true}],
       case mapred(Pid, Input, IdentityQuery, Timeout, CallTimeout) of
           {ok, [{_, Results}]} ->
               %% Unwrap the results.
  
positive.code:     %% Run a Map/Reduce operation using reduce_identity to get a list
      %% of BKeys.
      Input = {index, Bucket, Index, Key},
      IdentityQuery = [{reduce, {modfun, riak_kv_mapreduce, reduce_identity}, none, true}],
      case mapred(Pid, Input, IdentityQuery) of
          {ok, [{_, Results}]} ->
              %% Unwrap the results.
  
negative.code: search(Pid, Bucket, SearchQuery) ->
      %% Run a Map/Reduce operation using reduce_identity to get a list
      %% of BKeys.
      IdentityQuery = [{reduce,
                        {modfun, riak_kv_mapreduce, reduce_identity},
                        [{reduce_phase_only_1, true}],
                        true}],
      case search(Pid, Bucket, SearchQuery, IdentityQuery,
                  default_timeout(search_timeout)) of
          {ok, [{_, Results}]} ->
  