C#操作Oracle的CLOB列

Oracle clob列的大小超过32M时使用分割发送，小于32M时正常发送

 

 

Oracle clob列性能测试的测试用例：

 

using System;
using System.Collections.Generic;
using System.Text;
using System.Data;
using Oracle.DataAccess.Client;
using Oracle.DataAccess.Types;

namespace db
{
    class Program
    {
       // private OracleConnection mycon = new OracleConnection("Data Source=DB1;User Id = system;Password= asdf1234;");

        private OracleConnection mycon = new OracleConnection("Data Source=(DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=10.167.133.89)(PORT=1521))(CONNECT_DATA=(SERVICE_NAME=db1)));User Id = system;Password= asdf1234;");
        private OracleCommand mycom = null;

        private void open()
        {
            mycon.Open();
        }

        private void close()
        {
            mycon.Close();
        }

        private void delete() 
        {
            mycom = new OracleCommand("delete from system.tb1", mycon);
            mycom.ExecuteNonQuery();
        }
        
        private void insert(int num, Int32 length)
        {            
            
            String insertStr = "insert into system.tb1(CINT,CCLOB) values(:p1,:p2)";
            mycom = new OracleCommand(insertStr, mycon);
           
            string s = "a";
            DateTime dt1, dt2;
            OracleClob clob = null;
            OracleDataReader dr;
            
            if (length>=16)
            {                
                if (length == 128)
                {
                    for (int i = 0; i < 27; i++)
                    {
                        s += s;
                    }
                }
                else if (length == 32)
                {
                    for (int i = 0; i < 25; i++)
                    {
                        s += s;
                    }
                }
                else
                {                    
                    s = "";
                    string tmp = "a";
                    for (int i = 0; i < 20; i++)
                    {
                        tmp += tmp;
                    }
                    for (int j = 0; j < length; j++)
                    {
                        s += tmp;
                    }
                }
                dt1 = DateTime.Now;
                char[] charArray = null;
                for (int i = 0; i < num; i++)
                {
                    mycom.CommandText = "insert into system.tb1(CINT,CCLOB) values(" + i + ",'a')";
                    mycom.ExecuteNonQuery();
                    mycom.CommandText = "select CINT,CCLOB from system.tb1 where CINT=" + i;

                    dr = mycom.ExecuteReader();
                    dr.Read();
                    clob = dr.GetOracleClobForUpdate(1);
                    clob.Erase();
                    charArray = s.ToCharArray();
                    for (int j = charArray.Length; j >0; j -= 1024 * 1024)
                    {
                        clob.Write(charArray, 0, 1024 * 1024);
                    }

                }
                dt2 = DateTime.Now;

                mycom = new OracleCommand("select * from system.tb1", mycon);
                dr = mycom.ExecuteReader();
                dr.Read();
                Console.WriteLine(dr.GetOracleClob(1).Length / 1024 / 1024 / 2 + "M");
            }
            else
            {
                
                s = "";
                string tmp = "a";
                for (int i = 0; i < 20; i++)
                {
                    tmp += tmp;
                }
                for (int j = 0; j < length; j++)
                {
                    s += tmp;
                }
                dt1 = DateTime.Now;
                for (int i = 0; i < num; i++)
                {
                    mycom.Parameters.Clear();
                    /*
                    para1 = new OracleParameter("p1", OracleDbType.Int32);
                    para2 = new OracleParameter("p2", OracleDbType.Clob);
                    para1.Value = i;
                    para2.Value = s;
                    mycom.Parameters.Add(para1);
                    mycom.Parameters.Add(para2);
                     */
                    mycom.Parameters.Add("p1", OracleDbType.Int32).Value=i;
                    mycom.Parameters.Add("p2", OracleDbType.Clob).Value=s;
                    mycom.ExecuteNonQuery();
                }
                dt2 = DateTime.Now;

                mycom = new OracleCommand("select * from system.tb1", mycon);
                dr = mycom.ExecuteReader();
                dr.Read();
                Console.WriteLine(dr.GetString(1).Length / 1024 / 1024 + "M");
            }

            TimeSpan ts = dt2 - dt1;
            Console.Out.WriteLine("insert time: " + ts.TotalSeconds);
            
        }

        private void select(int num)
        {

            OracleDataReader dr = null;
            string selStr = ""; 
            mycom = new OracleCommand(selStr, mycon);
            DateTime dt1 = DateTime.Now;
            String s;
            for (int i = 0; i < num; i++)
            {
                mycom.CommandText = "select * from system.tb1 where CINT=" + i;
                dr = mycom.ExecuteReader();
                while(dr.Read())
                    s=dr.GetString(1);
                //Console.Out.WriteLine(s.ToString().Length);
                dr.Close();
            }
            DateTime dt2 = DateTime.Now;
            TimeSpan ts = dt2 - dt1;
            Console.Out.WriteLine("select time: " + ts.TotalSeconds);
        }
        

        static void Main(string[] args)
        {
            try
            {
                Program p = new Program();

                Console.Out.WriteLine("please input 3 parameters:");

                Console.Out.WriteLine("1.sql type (insert/select)");
                string sqlType;
                sqlType = Console.In.ReadLine();

                while (!sqlType.Equals("insert") && !sqlType.Equals("select"))
                {
                    Console.Out.WriteLine("sql type is not insert or select,please input insert or select");
                    sqlType = Console.In.ReadLine();
                }

                Console.Out.WriteLine("2.loop time");
                string loopNumStr = Console.In.ReadLine();
                int loopNum = 0;
                try
                {
                    loopNum=Convert.ToInt32(loopNumStr);
                }
                catch (System.Exception e)
                {
                    System.Console.WriteLine(e.Message.ToString());
                }

                Console.Out.WriteLine("3.data length(MB)");
                string dataLengthStr = Console.In.ReadLine();
                int dataLength = 0;
                try
                {
                    dataLength=Convert.ToInt32(dataLengthStr);
                }
                catch (System.Exception e)
                {
                    System.Console.WriteLine(e.Message.ToString());
                }

                p.open();

                if (sqlType.Equals("insert"))
                {
                    p.delete();
                    p.insert(loopNum, dataLength);
                }
                else if (sqlType.Equals("select"))
                {
                    p.select(loopNum);
                }
                p.close();

                Console.In.Read();
            }
            catch (System.Exception e)
            {
                System.Console.WriteLine(e.Message.ToString());
            }
        }

    }
}