Selektionsanweisung mit Parametern

public ArrayList getWeekPlan(string kapno, string woche)
{
   ArrayList weekPlan = new ArrayList();

   OleDbConnection conn = new OleDbConnection(
   "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=\\\\pfad1\\db.mdb");

   try
   {

      conn.Open();
      OleDbCommand comm = new OleDbCommand();
      comm.Connection = conn;
      comm.CommandText = "SELECT [Datum],[KapazitätNo] "+
      "FROM [qry_TagesAnsichtMengen] WHERE [KapazitätNo]=@kapno "+
      "AND [DINKW]=@woche";

      comm.Parameters.AddWithValue("kapno", kapno);
      comm.Parameters.AddWithValue("woche", woche);
      
      OleDbDataReader reader = comm.ExecuteReader();
      
       while (reader.Read())
       {
          WeekPlanVO vo = new WeekPlanVO();
          vo.datum = reader.GetValue(0).ToString();
          vo.menge = reader.GetValue(1).ToString();
          weekPlan.Add(vo);
        }
   }
   catch (Exception e)
   {
     WeekPlanVO vo = new WeekPlanVO();
     vo.datum = e.Message;
     vo.menge = e.Message;
     weekPlan.Add(vo);
     return weekPlan;
   }
   finally
   {
      conn.Close();
   }
  return weekPlan;
}

Manipulationsanweisung ohne Parameter

public string updateDetailDate(DateTime neuesDatum, DateTime altesDatum, 
string neueKW, string alteKW, string kapazitaet, string material, string beleg)
{
  OleDbConnection conn = new OleDbConnection(
  "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=\\\\pfad1\\db.mdb");

  
  try
  {
     conn.Open();
     OleDbCommand comm = new OleDbCommand();
     comm.Connection = conn;
     comm.CommandText = "UPDATE qry_Details_Akt SET [changed]=Now(), DinkW=" + neueKW + 
      ", WEWA_C='" + DateWrapper.GetServerDate(neuesDatum) + "', WEWA_C_OLD='" +
     DateWrapper.GetServerDate(altesDatum) + "' WHERE Beleg='" + beleg + 
     "'AND DinkW=" + alteKW + " AND Material='" + material + "' AND KapazitätNo=" + 
     kapazitaet;

     comm.ExecuteNonQuery();
  }
  catch (Exception e)
  {
      return e.Message+' '+e.StackTrace;
  }
  finally
  {
      conn.Close();
  }

  return "ok";
}