cartographer.ElectorateImporter.MergeDataPhaseTwo C# (CSharp) Method

        public List<Electorate> MergeDataPhaseTwo(List<Electorate> a_ElectorateData, string stateFederalRelationFilename, string federalElectionTPPHistoryFilename, string stateResultFilename)
        {
            OleDbConnection _connection = new OleDbConnection(@"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=data/db.mdb"); //!testing

            try
            {
                _connection.Open();
                OleDbCommand deleteCommand = new OleDbCommand("DELETE FederalElectorate.* FROM FederalElectorate;", _connection);
                deleteCommand.ExecuteNonQuery();
                _connection.Close();
                _connection.Open();
                foreach (var electorate in a_ElectorateData)
                {
                    string columns = "ID, ElectorateName, Actual, Projected, TotalPopulation, Over18, Area, ALPVotes, LPVotes, NPVotes, DEMVotes, GRNVotes, OTHVotes, LNP2PVotes, ALP2PVotes";
                    //string columns = "";//, TermsInPower, TPP";
                    string values = electorate.ID + ", '" + electorate.Name + "', " + electorate.Actual + ", " + electorate.Projected + ", " + electorate.TotalPopulation + ", " + electorate.Over18 + ", " + electorate.Area + ", " + electorate.ALPVotes + ", " + electorate.LPVotes + ", " + electorate.NPVotes + ", " + electorate.DEMVotes + ", " + electorate.GRNVotes + ", " + electorate.OTHVotes + ", " + electorate.LNP2PVotes + ", " + electorate.ALP2PVotes;
                    string command = "INSERT INTO [FederalElectorate] (" + columns + ") VALUES (" + values + ");";
                    OleDbCommand insertCommand = new OleDbCommand(command, _connection);

                    insertCommand.ExecuteNonQuery();
                }
            }
            finally
            {
                _connection.Close();
            }
            ParseStateFederalRelationalXLS(stateFederalRelationFilename);
            ParseFederalXLS(federalElectionTPPHistoryFilename);
            ParseStateResultsXLS(stateResultFilename);
            return null;
        }

        private void convertData_Click(object sender, EventArgs e)
        {
            ElectorateImporter g_elecImporter = new ElectorateImporter();
            try { g_elecImporter.ParseXLS(_xlsData); }
            catch { }
            try { g_elecImporter.ParseMID(_midData); }
            catch { }
            try { g_elecImporter.ParseMIF(_mifData); }
            catch { }
            m_Electorates = g_elecImporter.MergeData();
            g_elecImporter.MergeDataPhaseTwo(m_Electorates, "data/Qld_Federal-State Electorate Mapping.xls", "data/Federal Election Results-Qld-2004.xls", "data/Qld_State Results by Electorate-2006.xls"); //!TESTING
            convertPB.Image = (Image)pic.ResourceManager.GetObject("Tick");

               // m_Electorates[0].Name;
            for (int i =0; i < m_Electorates.Count; i++)
                pointBox.Items.Add(m_Electorates[i].Name, CheckState.Checked);
            g_Grabber = new DataGrabber();
            g_Grabber.importData();

            Exporter m_exporter = new Exporter(m_Electorates);
            m_exporter.convertToKml(colourMode);
            MessageBox.Show("Saved KML File from XLS and MID/MIF Data");
        }