总结C#连接数据库

Oracle

ODBC 方式

New version:
"Driver={Microsoft ODBC for Oracle};Server=OracleServer.world;Uid=Username;Pwd=****;" 

Old version:
"Driver={Microsoft ODBC Driver for Oracle};ConnectString=OracleServer.world;Uid=myUsername;Pwd=myPassword;"
 评价：ODBC连接速度较慢，技术层次属低层。

OracleConnection方式

标准：

Data Source=MyOracleDB;Integrated Security=yes;

指明 username and password：

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

说明：This one works only with Oracle 8i release 3 or later.

Missing the System.Data.OracleClient namespace? Download .NET Managed Provider for Oracle

评价：与 SqlConnection相比，OracleConnection相当于Baby。

当Oracle数据库的ORACLE_HOME安装在NTFS磁盘的时候，需要重新设置Authenticated Users用户的权限，否则在open连接的时候会Throw“System.Data.OracleClient requires Oracle client software version 8.1.7 or greater”异常。分析利弊，需要设置用户数据库服务器，也许会对原数据库有一定的影响。

Code:

using System.Data.OracleClient;

OracleConnection oOracleConn = new OracleConnection();
oOracleConn.ConnectionString = "my connectionstring";
oOracleConn.Open();

 

 

 OLEDB, OleDbConnection (.NET)

Standard Security：

Provider=msdaora;Data Source=MyOracleDB;User Id=UserName;Password=asdasd;

this one's from Microsoft, the following is from Oracle. 

Provider=OraOLEDB.Oracle;Data Source=MyOracleDB;User Id=Username;Password=asdasd;"

Trusted Connection:

Provider=OraOLEDB.Oracle;Data Source=MyOracleDB;OSAuthent=1b; //from Oracle.
说明：OLEDB是微软的战略性的通向不同的数据源的低级应用程序接口。不会出现上文中OracleConnection中出现异常。
Code：

using System.Data.OleDb;

OleDbConnection connection = new OleDbConnection(connectionString);
connection.Open();
OleDbCommand command = new OleDbCommand(sql);
command.Connection = connection;
OleDbDataReader reader = command.ExecuteReader();

http://www.connectionstrings.com/oracle 

http://blog.donews.com/kevinhlj/archive/2007/03/15/1140555.aspx