anchor.diff:  
   %%
   execute_query({query, ReceiverPid, QId, [Qry1|_] = SubQueries, _DDL, QBufRef},
  -              #state{ run_sub_qs_fn = RunSubQs } = State) ->
  +              State) ->
       Indices = lists:seq(1, length(SubQueries)),
       ZQueries = lists:zip(Indices, SubQueries),
       %% all subqueries have the same select clause
  
positive.code:           sub_qrys      = []                  :: [integer()],
            receiver_pid                        :: pid(),
            result        = []                  :: rows_acc() | aggregate_acc() | group_by_acc(),
            run_sub_qs_fn = fun run_sub_qs_fn/1 :: fun(),
            qbuf_ref                            :: undefined | riak_kv_qry_buffers:qbuf_ref(),
            orig_qry                            :: undefined | ?SQL_SELECT{}
           }).
  
negative.code:                 InitialState
          end,
      SubQs = [{{qry, Q}, {qid, {I, QId}}} || {I, Q} <- ZQueries],
      ok = run_sub_qs_fn(SubQs),
      {ok, State#state{qid          = QId,
                       receiver_pid = ReceiverPid,
                       qry          = Qry1,
  