Trabalhar com dados em memória

procedure TFrmAgenda.CarregaHorarios(f_Data: TDate);
var
  X: Integer;
  HoraIni: TTime;
begin
  // Abre e fecha o componente de memoria
  cdsHorarios.Close;
  cdsHorarios.IsEmpty;
  cdsHorarios.CreateDataSet;
  cdsHorarios.Open;

  // Procedimento de inicio de hora
  HoraIni := StrToTime('07:15');

  // For para ir das 08:00 as 11:45 e 13:30 as 20:15
  for X := 1 to 16 do
  begin
    HoraIni := IncMinute(HoraIni, 45);
    //Contando os registros pra colorir o grid horarios
    with qrCont do
    begin
      Close;
      SQL.Clear;
      SQL.Add('SELECT DATA, HORA FROM AGENDA');
      SQL.Add('WHERE HORA = :H AND DATA = :D');
      ParamByName('H').AsTime := HoraIni;
      ParamByName('D').AsDate := Calendario.Date;
      Open;
      FetchAll;
    end;

    cdsHorarios.Append;
    cdsHorarios.FieldByName('HORA').AsDateTime := HoraIni;
    cdsHorarios.FieldByName('QTDE').AsInteger  := qrCont.RecordCount; 
    cdsHorarios.Post;

    if HoraIni = StrToTime('11:45') then
       HoraIni := IncMinute(HoraIni, 60);
  end;

  cdsHorarios.First;
  GridHorariosCellClick(GridHorarios.Columns[0]); //Mostra a agenda do 1º registro
end;

   with frmdm.qrAgenda do
   begin
     Close;
     SQL.Clear;
     SQL.Add('SELECT * FROM AGENDA');
     SQL.Add('WHERE HORA = :H AND DATA = :D');
     ParamByName('H').AsTime:= cdsHorariosHORA.AsDateTime;
     ParamByName('D').AsDate:= Calendario.Date;
     Open;
   end;