如何高效的将excel导入到oracle

如何高效的将excel导入到oracle?和前两天的SqlBulkCopy 导入到sqlserver对应,oracle也有自身的方法,只是稍微复杂些.
那就是使用oracle的sql*loader功能，而sqlldr只支持类似csv格式的数据，所以要自己把excel转换一下。
实现步骤：
用com组件读取excel-保存为csv格式-处理最后一个字段为null的情况和表头-根据excel结构建表-生成sqlldr的控制文件-用sqlldr命令导入数据
这个性能虽然没有sql的bcp快，但还是相当可观的，在我机器上1万多数据不到4秒，而且导入过程代码比较简单，也同样没有循环拼接sql插入那么难以维护。

这里也提个问题:处理csv文件的表头和最后一个字段为null的情况是否可以优化？除了我代码中的例子，我实在想不出其他办法。

 

using System;
using System.Data;
using System.Text;
using System.Windows.Forms;
using Microsoft.Office.Interop.Excel;
using System.Data.OleDb;
//引用-com-microsoft excel objects 11.0
namespace WindowsApplication5
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        /// <SUMMARY>
        /// excel导入到oracle
        /// </SUMMARY>
        /// <PARAM name="excelFile">文件名</PARAM>
        /// <PARAM name="sheetName">sheet名</PARAM>
        /// <PARAM name="sqlplusString">oracle命令sqlplus连接串</PARAM>
        public void TransferData(string excelFile, string sheetName, string sqlplusString)
        {
            string strTempDir = System.IO.Path.GetDirectoryName(excelFile);
            string strFileName = System.IO.Path.GetFileNameWithoutExtension(excelFile);
            string strCsvPath = strTempDir +"\\"+strFileName + ".csv";
            string strCtlPath = strTempDir + "\\" + strFileName + ".Ctl";
            string strSqlPath = strTempDir + "\\" + strFileName + ".Sql";
            if (System.IO.File.Exists(strCsvPath))
                System.IO.File.Delete(strCsvPath);


            //获取excel对象
            Microsoft.Office.Interop.Excel.Application ObjExcel = new Microsoft.Office.Interop.Excel.Application();

            Microsoft.Office.Interop.Excel.Workbook ObjWorkBook;

            Microsoft.Office.Interop.Excel.Worksheet ObjWorkSheet = null;

            ObjWorkBook = ObjExcel.Workbooks.Open(excelFile, Type.Missing, Type.Missing, Type.Missing, Type.Missing, Type.Missing, Type.Missing, Type.Missing, Type.Missing, Type.Missing, Type.Missing, Type.Missing, Type.Missing, Type.Missing, Type.Missing);

            foreach (Microsoft.Office.Interop.Excel.Worksheet sheet in ObjWorkBook.Sheets)
            {
                if (sheet.Name.ToLower() == sheetName.ToLower())
                {
                    ObjWorkSheet = sheet;
                    break;
                }
            }
            if (ObjWorkSheet == null) throw new Exception(string.Format("{0} not found!!", sheetName));


            //保存为csv临时文件
            ObjWorkSheet.SaveAs(strCsvPath, Microsoft.Office.Interop.Excel.XlFileFormat.xlCSV, Type.Missing, Type.Missing, false, false, false, Type.Missing, Type.Missing, false);
            ObjWorkBook.Close(false, Type.Missing, Type.Missing);
            ObjExcel.Quit();

            //读取csv文件，需要将表头去掉，并且将最后一列为null的字段处理为显示的null，否则oracle不会识别，这个步骤有没有好的替换方法?
            System.IO.StreamReader reader = new System.IO.StreamReader(strCsvPath,Encoding.GetEncoding("gb2312"));
            string strAll = reader.ReadToEnd();
            reader.Close();
            string strData = strAll.Substring(strAll.IndexOf("\r\n") + 2).Replace(",\r\n",",Null");

            byte[] bytes = System.Text.Encoding.Default.GetBytes(strData);
            System.IO.Stream ms = System.IO.File.Create(strCsvPath);
            ms.Write(bytes, 0, bytes.Length);
            ms.Close();


            //获取excel表结构
            string strConn = "Provider=Microsoft.Jet.OLEDB.4.0;" + "Data Source=" + excelFile + ";" + "Extended Properties=Excel 8.0;";
            OleDbConnection conn = new OleDbConnection(strConn);
            conn.Open();
            System.Data.DataTable table = conn.GetOleDbSchemaTable(System.Data.OleDb.OleDbSchemaGuid.Columns,
                new object[] { null, null, sheetName+"$", null });


            //生成sqlldr用到的控制文件,文件结构参考sql*loader功能，本示例已逗号分隔csv，数据带逗号的用引号括起来。
            string strControl =  "load data\r\ninfile &apos;{0}&apos; \r\nappend into table {1}\r\n"+
　　                "FIELDS TERMINATED BY &apos;,&apos; OPTIONALLY ENCLOSED BY &apos;\"&apos;\r\n(";
            strControl = string.Format(strControl, strCsvPath,sheetName);
            foreach (System.Data.DataRow drowColumns in table.Select("1=1", "Ordinal_Position"))
            {
                strControl += drowColumns["Column_Name"].ToString() + ",";
            }

            strControl = strControl.Substring(0, strControl.Length - 1) + ")";
            bytes=System.Text.Encoding.Default.GetBytes(strControl);
            ms= System.IO.File.Create(strCtlPath);

            ms.Write(bytes, 0, bytes.Length);
            ms.Close();

            //生成初始化oracle表结构的文件
            string strSql = @"drop table {0};
　　                create table {0}
　　                (";
            strSql = string.Format(strSql, sheetName);
            foreach (System.Data.DataRow drowColumns in table.Select("1=1", "Ordinal_Position"))
            {
                strSql += drowColumns["Column_Name"].ToString() + " varchar2(255),";
            }
            strSql = strSql.Substring(0, strSql.Length - 1) + ");\r\nexit;";
            bytes = System.Text.Encoding.Default.GetBytes(strSql);
            ms = System.IO.File.Create(strSqlPath);

            ms.Write(bytes, 0, bytes.Length);
            ms.Close();


            //运行sqlplus，初始化表
            System.Diagnostics.Process p = new System.Diagnostics.Process();
            p.StartInfo = new System.Diagnostics.ProcessStartInfo();
            p.StartInfo.FileName = "sqlplus";
            p.StartInfo.Arguments = string.Format("{0} @{1}", sqlplusString, strSqlPath);
            p.StartInfo.WindowStyle = System.Diagnostics.ProcessWindowStyle.Hidden;
            p.StartInfo.UseShellExecute = false;
            p.StartInfo.CreateNoWindow = true;
            p.Start();
            p.WaitForExit();

            //运行sqlldr，导入数据
            p = new System.Diagnostics.Process();
            p.StartInfo = new System.Diagnostics.ProcessStartInfo();
            p.StartInfo.FileName = "sqlldr";
            p.StartInfo.Arguments = string.Format("{0} {1}", sqlplusString, strCtlPath);
            p.StartInfo.WindowStyle = System.Diagnostics.ProcessWindowStyle.Hidden;
            p.StartInfo.RedirectStandardOutput = true;
            p.StartInfo.UseShellExecute = false;
            p.StartInfo.CreateNoWindow = true;
            p.Start();
            System.IO.StreamReader r = p.StandardOutput;//截取输出流
            string line = r.ReadLine();//每次读取一行
            textBox3.Text += line + "\r\n";
            while (!r.EndOfStream)
            {
                line = r.ReadLine();
                textBox3.Text += line + "\r\n";
                textBox3.Update();
            }
            p.WaitForExit();

            //可以自行解决掉临时文件csv，ctl和sql，代码略去
        }

        private void button1_Click(object sender, EventArgs e)
        {
            TransferData(@"D:\test.xls", "Sheet1", "username/password@servicename");
        }

    }
}