delphi
procedure TForm4.ComboBox1Change(Sender: TObject); var A : String; begin if (ComboBox1.Text='ENTRADA') THEN begin query.Close; query.SQL.Text:='SELECT folio FROM entradas ORDER BY folio desc LIMIT 1'; query.Open; folio.text := IntToStr(query.FieldByName('folio').asInteger +1); end else begin if (ComboBox1.Text='SALIDAS') THEN query.Close; query.SQL.Text:='SELECT folio2 FROM entradas ORDER BY folio2 desc LIMIT 1'; query.Open; folio.text := IntToStr(query.FieldByName('folio2').asInteger +1) ; end;