How to Access Oracle Eloqua Reporting Data Using Entity Framework

Microsoft Entity Framework serves as an object-relational mapping framework for working with data represented as objects. Although Visual Studio offers the ADO.NET Entity Data Model wizard to automatically generate the Entity Model, this model-first approach may present challenges when your data source undergoes changes or when you require greater control over entity operations. In this article, we will delve into the code-first approach for accessing Oracle Eloqua Reporting data through the CData ADO.NET Provider, providing you with more flexibility and control.

1. Open Visual Studio and create a new Windows Form Application. This article uses a C# project with .NET 4.5.
2. Run the command 'Install-Package EntityFramework' in the Package Manger Console in Visual Studio to install the latest release of Entity Framework.

3. Modify the App.config file in the project to add a reference to the Oracle Eloqua Reporting Entity Framework 6 assembly and the connection string.

   Oracle Eloqua Reporting supports the following authentication methods:

   • Basic authentication (User and Password)
   • OAuth 2.0 code grant flow
   • OAuth 2.0 password grant flow

   Basic Authentication (User and Password)

   To perform authentication with a user and password, specify these properties:

   • AuthScheme: Basic.
   • Company: The company name associated with your Oracle Eloqua Reporting account.
   • User: Your login account name.
   • Password: Your login password.

   OAuth Authentication (Code Grant Flow)

   To authenticate with the OAuth code grant flow, you must set AuthScheme to OAuth and create a custom OAuth application. For information about how to create a custom OAuth application, see the Help documentation.

   Then set the following properties:

   • InitiateOAuth: GETANDREFRESH. Used to automatically get and refresh the OAuthAccessToken.
   • OAuthClientId: The client Id assigned when you registered your application.
   • OAuthClientSecret: The client secret that was assigned when you registered your application.
   • CallbackURL: The redirect URI that was defined when you registered your application.

   When you connect, the driver opens Oracle Eloqua Reporting's OAuth endpoint in your default browser. Log in and grant permissions to the application. When the access token expires, the driver refreshes it automatically.

   OAuth Authentication (Password Grant Flow)

   With the OAuth password grant flow, you can use your OAuth application's credentials alongside your user credentials to authenticate without the need to grant permission manually via a browser prompt. You must create an OAuth app (see the Help documentation) to use this authentication method.

   Set the following properties:

   • AuthScheme: OAuthPassword
   • Company: The company's unique identifier.
   • User: Your login account name.
   • Password: Your login password.
   • OAuthClientId: The client Id assigned when you registered your custom OAuth application.
   • OAuthClientSecret: The client secret assigned when you registered your custom OAuth application.

   
   <configuration>
      ... 
     <connectionStrings>
       <add name="OracleEloquaReportingContext" connectionString="Offline=False;AuthScheme=Basic;User=user;Password=password;Company=MyCompany;" providerName="System.Data.CData.OracleEloquaReporting" />
     </connectionStrings>
     <entityFramework>
       <providers>
          ... 
         <provider invariantName="System.Data.CData.OracleEloquaReporting" type="System.Data.CData.OracleEloquaReporting.OracleEloquaReportingProviderServices, System.Data.CData.OracleEloquaReporting.Entities.EF6" />
       </providers>
     <entityFramework>
   </configuration>
   </code> 
   

4. Add a reference to System.Data.CData.OracleEloquaReporting.Entities.EF6.dll, located in the lib -> 4.0 subfolder in the installation directory.
5. Build the project at this point to ensure everything is working correctly. Once that's done, you can start coding using Entity Framework.
6. Add a new .cs file to the project and add a class to it. This will be your database context, and it will extend the DbContext class. In the example, this class is named OracleEloquaReportingContext. The following code example overrides the OnModelCreating method to make the following changes:
   • Remove PluralizingTableNameConvention from the ModelBuilder Conventions.
   • Remove requests to the MigrationHistory table.

   
   using System.Data.Entity;
   using System.Data.Entity.Infrastructure;
   using System.Data.Entity.ModelConfiguration.Conventions;
   
   class OracleEloquaReportingContext : DbContext {
     public OracleEloquaReportingContext() { }
   
     protected override void OnModelCreating(DbModelBuilder modelBuilder)
     {
       // To remove the requests to the Migration History table
       Database.SetInitializer<OracleEloquaReportingContext>(null);  
       // To remove the plural names    
       modelBuilder.Conventions.Remove<PluralizingTableNameConvention>();
     }  
   }
   

7. Create another .cs file and name it after the Oracle Eloqua Reporting entity you are retrieving, for example, . In this file, define both the Entity and the Entity Configuration, which will resemble the example below:

   
   using System.Data.Entity.ModelConfiguration;
   using System.ComponentModel.DataAnnotations.Schema;
   
   [System.ComponentModel.DataAnnotations.Schema.Table("")]
   public class  {
     [System.ComponentModel.DataAnnotations.Key] 
     public System.String  { get; set; }
     public System.String  { get; set; }
   }
       
   

8. Now that you have created an entity, add the entity to your context class:

   
   public DbSet<>  { set; get; }
   

9. With the context and entity finished, you are now ready to query the data in a separate class. For example:

   OracleEloquaReportingContext context = new OracleEloquaReportingContext();
   context.Configuration.UseDatabaseNullSemantics = true;
   var query = from line in context. select line;