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c#中高效的excel导入oracle的方法

2009年04月21日 星期二 下午 07:57

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();

        }

 

        ///

        /// excel导入到oracle

        ///

        /// 文件名

        /// sheet

        /// oracle命令sqlplus连接串

        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 '{0}' \r\nappend into table {1}\r\n"+   

                  "FIELDS TERMINATED BY ',' OPTIONALLY ENCLOSED BY '\"'\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");

        }

       

    }

}

 

posted on 2010-06-30 10:39  牵匹瘦驴  阅读(521)  评论(0)    收藏  举报