c# - これを行うより良い方法はありますか？

Question

ここに行きます。問題なく動作するデータセットのモデルがあり、データベースからデータをインポートして Crystal レポートに渡します。このソリューションは機能しますが、非常に時間がかかります。これを行う他の方法があるかどうか疑問に思っていました...

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using Oracle.DataAccess.Client;
using System.Data;
using CrystalDecisions.CrystalReports.Engine;
using CrystalDecisions.Shared;


namespace WebApplication1
{
    public partial class WebForm1 : System.Web.UI.Page
    {
        protected void Page_Load(object sender, EventArgs e)
        {

        }

        protected void Button1_Click(object sender, EventArgs e)
        {
            string connetionString = null;
            OracleConnection connection;
            OracleDataAdapter OracleAdapter;
            DataSet ds = new DataSet();
            string firstSql = null;


            connetionString = "datasoruce";

            connection = new OracleConnection(connetionString);
               string secondSql = "select statementnumber from erocks.statement_data_domestic";
                connection.Open();
                //OracleAdapter = new OracleDataAdapter(firstSql, connection);
                //OracleAdapter.Fill(ds, "domestic");
                OracleAdapter = new OracleDataAdapter(secondSql, connection);
                OracleAdapter.Fill(ds, "statement");
                connection.Close();
                ReportDocument reportDoc = new ReportDocument();
                reportDoc.Load(@"c:\users\desktop\statement.rpt");


            DataTable stmt = ds.Tables["statement"];

            string stmtnumber="";
            for (int i = 0; i < stmt.Rows.Count - 1; i++)
            {
                stmtnumber = stmt.Rows[i][0].ToString();

                firstSql = @"SELECT DISTINCT statement_header.statementnumber,
                     statement_details.invoicedate,
                     statement_details.invoicenumber,
                     statement_details.invoicetotal,
                     statement_details.doc_type,
                     statement_header.statementtotal,
                     statement_details.bunumber_ru,
                     statement_details.bunumber,
                     statement_details.description,
                     statement_details.reference_number,
                     statement_header.remto_zip,
                     statement_header.remto_city,
                     statement_header.remto_state,
                     statement_header.remto_mailname,
                     statement_header.remto_addr1,
                     statement_header.remto_addr2,
                     statement_header.remto_addr3,
                     statement_header.soldto_city,
                     statement_header.soldto_state,
                     statement_header.soldto_zip,
                     statement_header.soldto_addr1,
                     statement_header.soldto_addr2,
                     statement_header.soldto_addr3,
                     statement_header.balance_forward,
                     statement_header.statementdate,
                     statement_header.custid,
                     statement_header.custname,
                     statement_header.phone_prefix,
                     statement_header.phone_number,
                     statement_details.purchases,
                     statement_details.payments,
                     statement_details.misc_credit2,
                     statement_details.misc_credit1,
                     statement_header.company_number,
                     statement_header.statementpurchases,
                     statement_header.statementpayments,
                     statement_header.statementmisc_credit1,
                     statement_header.statementmisc_credit2,
                     statement_header.nomailnoprint,
                     statement_header.SOLDTOCOUNTRYCODE,
                     statement_header.SOLDTOCOUNTRYNAME,
                     statement_header.CREDITZEROFLAG
       FROM STATEMENT_DATA_DOMESTIC statement_header
            INNER JOIN STATEMENT_DATA_DETAILS statement_details
               ON statement_header.statementnumber =
                     statement_details.statementnumber
                        where statement_header.statementnumber="+stmtnumber;
                connection.Open();
                OracleAdapter = new OracleDataAdapter(firstSql, connection);
                OracleAdapter.Fill(ds, "domestic");

                OracleAdapter.Dispose();
                connection.Close();
                reportDoc.SetDataSource(ds.Tables["domestic"]);
                ExportOptions CrExportOptions;
                DiskFileDestinationOptions CrDiskFileDestinationOptions = new DiskFileDestinationOptions();
                PdfRtfWordFormatOptions CrFormatTypeOptions = new PdfRtfWordFormatOptions();
                CrDiskFileDestinationOptions.DiskFileName = @"d:\pdf\"+ stmtnumber + ".pdf";
                CrExportOptions = reportDoc.ExportOptions;
                {
                    CrExportOptions.ExportDestinationType = ExportDestinationType.DiskFile;
                    CrExportOptions.ExportFormatType = ExportFormatType.PortableDocFormat;
                    CrExportOptions.DestinationOptions = CrDiskFileDestinationOptions;
                    CrExportOptions.FormatOptions = CrFormatTypeOptions;

                }
                reportDoc.Export();
                ds.Tables["domestic"].Clear();
            }
                }
            }

        }