if DBGridEh1.SelectedRows.Count > 0 then
  // Мультиселект
    begin
      with ADQuery1 do
        begin
          for i := 0 to DBGridEh1.SelectedRows.Count - 1 do
            begin
              GotoBookmark(pointer(DBGridEh1.SelectedRows.Items[i]));
              s := s + FieldByName('id').AsString + ',';
            end;
        end;

  ADQuery1.DisableControls;
  while not ADQuery1.Eof do
    begin
      if ADQuery1.FieldByName('chk').AsString = 'Y' then
        DBGridEh1.SelectedRows.CurrentRowSelected := true;
      ADQuery1.Next;
    end;
  ADQuery1.First;
  ADQuery1.EnableControls;