'Listing 34.5  34LIST05.TXT  -- Programowe sprawdzanie unikalnoci klucza

  SQLSTR = "Select * from Lineitem where chnum = " & ent_chknumber.Text
  Set ChkSet = ChkDb.OpenRecordSet (SQLSTR, dbOpenDynaset)
  If not (ChkSet.EOF and ChkSet.BOF) Then
    MsgBox "Rekord o podanym kluczu ju istnieje!" + Chr(13) + "Wprowad inny klucz", vbCritical, App.Title
       Exit Sub
  End If
  ChkSet.Close

