anchor.diff:                  queue = queue:new(),
                   async,
                   parameters = [],
  -                statement,
  +                types = [],
                   columns = [],
                   rows = [],
                   results = [],
  
positive.code:         {_, {squery, _}} ->
              Columns
      end.
  
  sync_required(#state{queue = Q} = State) ->
      case queue:is_empty(Q) of
  
negative.code:     {{From, Ref}, _} = queue:get(Q),
      From ! {Ref, Message},
      State#state{queue = queue:drop(Q),
                  types = [],
                  columns = [],
                  rows = [],
                  results = []}.
  
  add_result(State = #state{results = Results}, Result) ->
      State#state{types = [],
                  columns = [],
                  rows = [],
                  results = [Result | Results]}.
  