演示如何从DataSet中获取LOB数据

演示如何从DataSet中获取LOB数据。


using System;


using System.Collections.Generic;


using System.Text;


using System.Data;


using Oracle.DataAccess.Client;


using Oracle.DataAccess.Types;




namespace Sample11






{




/**//// <summary>


/// 演示如何从DataSet中获取LOB数据


/// </summary>


class Program






{




static void Main(string[] args)






{


// connect


string constr = "User Id=scott;Password=tiger;Data Source=(DESCRIPTION =(ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.1.24)(PORT = 1521))(CONNECT_DATA = (SERVER = DEDICATED)(SERVICE_NAME = bjoracle.oracle10g.mynet)))";


OracleConnection conn = Connect(constr);




// setup the table and data


Setup(conn);




// Create the oracleCommand


OracleCommand cmd = new OracleCommand("SELECT story FROM multimedia_tab");


cmd.Connection = conn;


cmd.CommandType = CommandType.Text;




// Create the OracleDataAdapter


OracleDataAdapter da = new OracleDataAdapter(cmd);




// Dataset


DataSet ds = new DataSet();


try






{


da.FillSchema(ds, SchemaType.Source, "Media");




// Fill data


da.Fill(ds, "Media");




// Obtain LOB data


Console.WriteLine(ds.Tables["Media"].Rows[0]["story"]);


}


catch (Exception ex)






{


Console.WriteLine("ERROR: {0}", ex.Message);


}


finally






{


// Dispose OracleCommand


cmd.Dispose();




// Close and Dispose OracleConnection object


conn.Close();


conn.Dispose();


}




Console.ReadLine();


}






/**//// <summary>


/// 打开数据库连接


/// </summary>


/// <param name="connectStr"></param>


/// <returns></returns>


public static OracleConnection Connect(string connectStr)






{


OracleConnection conn = new OracleConnection(connectStr);


try






{


conn.Open();


}


catch (Exception ex)






{


Console.WriteLine("Error: {0}", ex.Message);


}


return conn;


}






/**//// <summary>


/// 创建必要的表和测试数据


/// </summary>


/// <param name="conn"></param>


public static void Setup(OracleConnection conn)






{


StringBuilder blr;


OracleCommand cmd = new OracleCommand("", conn);




blr = new StringBuilder();


blr.Append("DROP TABLE multimedia_tab");


cmd.CommandText = blr.ToString();


try






{


cmd.ExecuteNonQuery();


}


catch (Exception ex)






{


Console.WriteLine("Error: {0}", ex.Message);


}




blr = new StringBuilder();


blr.Append("CREATE TABLE multimedia_tab(thekey NUMBER(4) PRIMARY KEY,");


blr.Append("story CLOB, sound BLOB)");


cmd.CommandText = blr.ToString();


try






{


cmd.ExecuteNonQuery();


}


catch (Exception ex)






{


Console.WriteLine("Error: {0}", ex.Message);


}




blr = new StringBuilder();


blr.Append("INSERT INTO multimedia_tab values(");


blr.Append("1,");


blr.Append("'This is a long story. Once upon a time

',");


blr.Append("'65645444564113418787311578783121548787878')");


cmd.CommandText = blr.ToString();


try






{


cmd.ExecuteNonQuery();


}


catch (Exception ex)






{


Console.WriteLine("Error: {0}", ex.Message);


}


}


}


}



在学习例子的过程中想到了如何利用 Oracle.DataAccess.Client.OracleConnection 连接远程服务器的服务，就像SQL Server一样指定IP，这里需要的只是将tnsnames.ora中的连接信息拷贝过来就可以了。
这里对 .NET 连接 oracle 数据库 做些总结：

1、ODBC


//New version


Driver={Microsoft ODBC for Oracle};Server=myServerAddress;Uid=myUsername;Pwd=myPassword;






//Old version


Driver={Microsoft ODBC Driver for Oracle};ConnectString=OracleServer.world;Uid=myUsername;Pwd=myPassword;



2、OLE DB, OleDbConnection (.NET)


//Standard security This connection string uses a provider from Microsoft.


Provider=msdaora;Data Source=MyOracleDB;User Id=myUsername;Password=myPassword;




//Trusted connection


Provider=msdaora;Data Source=MyOracleDB;Persist Security Info=False;Integrated Security=Yes;




//Standard Security This connection string uses a provider from Oracle.


Provider=OraOLEDB.Oracle;Data Source=MyOracleDB;User Id=myUsername;Password=myPassword;




//Trusted Connection


Provider=OraOLEDB.Oracle;Data Source=MyOracleDB;OSAuthent=1;
3、Oracle.DataAccess.Client.OracleConnection


//Standard


Data Source=TORCL;User Id=myUsername;Password=myPassword;




//Using integrated security


Data Source=TORCL;Integrated Security=SSPI;




//Using ODP.NET without tnsnames.ora


Data Source=(DESCRIPTION=(ADDRESS_LIST=(ADDRESS=(PROTOCOL=TCP)(HOST=MyHost)(PORT=MyPort)))(CONNECT_DATA=(SERVER=DEDICATED)(SERVICE_NAME=MyOracleSID)));User Id=myUsername;Password=myPassword;
4、OracleConnection, Oracle Data Provider, ODP.NET, System.Data.OracleClient.OracleConnection


// Standard


Data Source=MyOracleDB;Integrated Security=yes;




// Specifying username and password


Data Source=MyOracleDB;User Id=myUsername;Password=myPassword;Integrated Security=no;




// Omiting tnsnames.ora


SERVER=(DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=MyHost)(PORT=MyPort))(CONNECT_DATA=(SERVICE_NAME=MyOracleSID)));uid=myUsername;pwd=myPassword;




Data Source=(DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=MyHost)(PORT=MyPort))(CONNECT_DATA=(SERVICE_NAME=MyOracleSID)));User Id=myUsername;Password=myPassword;




// Using Connection Pooling


Data Source=myOracleDB;User Id=myUsername;Password=myPassword;Min Pool Size=10;Connection Lifetime=120;Connection Timeout=60;Incr Pool Size=5;Decr Pool Size=2;




// Windows Authentication


Data Source=myOracleDB;User Id=/;




// Privileged Connection With SYSDBA privileges


Data Source=myOracleDB;User Id=SYS;Password=SYS;DBA Privilege=SYSDBA;




// Privileged Connection With SYSOPER privileges


Data Source=myOracleDB;User Id=SYS;Password=SYS;DBA Privilege=SYSOPER;




// Utilizing the Password Expiration functionality


Data Source=myOracleDB;User Id=myUsername;Password=myPassword;


oConn.OpenWithNewPassword(sTheNewPassword);




// Proxy Authentication


Data Source=myOracleDB;User Id=myUsername;Password=myPassword;Proxy User Id=pUserId;Proxy Password=pPassword;
5、Core Labs OraDirect (.NET)


// Standard


User ID=myUsername;Password=myPassword;Host=ora;Pooling=true;Min Pool Size=0;Max Pool Size=100;Connection Lifetime=0;
6、Data Shape


// MS Data Shape


Provider=MSDataShape.1;Persist Security Info=False;Data Provider=MSDAORA;Data Source=orac;User Id=myUsername;Password=myPassword;

更多的信息请参见：http://www.connectionstrings.com/