Connecting to Oracle using Oracle.ManagedDataAccess

Question

I am using Oracle.ManagedDataAccess Nuget Package Version 12.1.022 in my C# (.NET 4.0) project. The package automatically creates entries in the app.config file. How can I read the datasource string from this file to be able to connect to the data base?

System.Configuration.ConfigurationManager.AppSettings.Get("dataSource");

is not working for me

<?xml version="1.0" encoding="utf-8"?>

<configuration>
  <configSections>
    <section name="oracle.manageddataaccess.client"
             type="OracleInternal.Common.ODPMSectionHandler, Oracle.ManagedDataAccess, Version=4.121.2.0, Culture=neutral, PublicKeyToken=89b483f429c47342" />
  </configSections>
  <system.data>
    <DbProviderFactories>
      <remove invariant="Oracle.ManagedDataAccess.Client" />
      <add name="ODP.NET, Managed Driver" invariant="Oracle.ManagedDataAccess.Client"
           description="Oracle Data Provider for .NET, Managed Driver"
           type="Oracle.ManagedDataAccess.Client.OracleClientFactory, Oracle.ManagedDataAccess, Version=4.121.2.0, Culture=neutral, PublicKeyToken=89b483f429c47342" />
    </DbProviderFactories>
  </system.data>
  <runtime>
    <assemblyBinding xmlns="urn:schemas-microsoft-com:asm.v1">
      <dependentAssembly>
        <publisherPolicy apply="no" />
        <assemblyIdentity name="Oracle.ManagedDataAccess" publicKeyToken="89b483f429c47342" culture="neutral" />
        <bindingRedirect oldVersion="4.121.0.0 - 4.65535.65535.65535" newVersion="4.121.2.0" />
      </dependentAssembly>
    </assemblyBinding>
  </runtime>

  <oracle.manageddataaccess.client>
    <version number="*">
      <dataSources>
        <dataSource alias="MyDataSource"
                    descriptor="(DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=100.100.100.100)(PORT=1521))(CONNECT_DATA=(SERVICE_NAME=myservice.com)))" />
      </dataSources>
    </version>
  </oracle.manageddataaccess.client>
</configuration>

Answer 1

Typically, you would refer to the alias in a standard connection string:

  <connectionStrings>
    <add name="MyConnection" connectionString="Data Source=MyDataSource;User Id=scott;Password=tiger;"/>
  </connectionStrings>

Then you would use the standard method for retrieving the string:

ConfigurationManager.ConnectionStrings["MyConnection"].ConnectionString;

Also keep in mind that the data source section is optional. You can embed the descriptor directly in the connection string:

  <connectionStrings>
    <add name="MyConnection" connectionString="Data Source=(DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=100.100.100.100)(PORT=1521))(CONNECT_DATA=(SERVICE_NAME=myservice.com)));User Id=scott;Password=tiger;"/>
  </connectionStrings>

You can also refer to aliases in a tnsnames.ora file. By default the driver looks for a tnsnames.ora in the exe folder, a directory specified in a TNS_ADMIN environment variable, or the TNS_ADMIN config variable:

http://docs.oracle.com/cd/E48297_01/doc/win.121/e41125/featConfig.htm#autoId6 http://docs.oracle.com/cd/E48297_01/doc/win.121/e41125/featConfig.htm#autoId7

Answer 2

You can refer to the already defined datasource in the connection string

<oracle.manageddataaccess.client>
    <version number="*">
        <dataSources>
            <dataSource alias="MyDataSource" descriptor="(DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=100.100.100.100)(PORT=1521))(CONNECT_DATA=(SERVICE_NAME=myservice.com)))" />
        </dataSources>
    </version>
</oracle.manageddataaccess.client>

for instance, in this specific case:

public class OracleDBManager
{
    private OracleConnection _con;
    private const string connectionString = "User Id={0};Password={1};Data Source=MyDataSource;";
    private const string OracleDBUser = "exampleUser";
    private const string OracleDBPassword = "examplePassword";

    public OracleDBManager()
    {
        InitializeDBConnection();
    }

    ~OracleDBManager()
    {
        if (_con != null)
        {
            _con.Close();
            _con.Dispose();
            _con = null;
        }
    }

    private void InitializeDBConnection()
    {
            _con = new OracleConnection();
            _con.ConnectionString = string.Format(connectionString, OracleDBUser, OracleDBPassword);
            _con.Open();
    }
}

Answer 3

You can make a separate class file returning the connectionstring like this -

public static OracleConnection GetConnection()
{
  const string connectionString = "Data Source=(DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=127.0.0.1)(PORT=1521)) (CONNECT_DATA=(SERVICE_NAME=PROD))); User Id=userId;Password=password;";
  var connection=new OracleConnection(connectionString);
  return connection;
}

Then you can call it like this where you need to access oracle db-

var oracleConnection = OracleDbConnection.GetConnection();
oracon.Open();

Answer 4

Using the package Formo, I created following method to get the MyDataSource string from app.config file

using Configuration = Formo.Configuration;
.......
/// <summary>
/// Gets the data source from app.config file
/// </summary>
/// <returns></returns>
public string GetMyDataSource()
{
    dynamic config = new Configuration();
    return config.MyDataSource;
}