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What's New in ADO.NET

The following features are new in ADO.NET with the .NET Framework version 4.

ADO.NET Entity Framework

The Entity Framework decreases the amount of coding and maintenance required for data-driven applications by enabling you to program against data models defined in terms of entities and relationships. For more information, see Entity Framework Overview.

The features described below are new to the Entity Framework in .NET Framework 4.

Foreign Keys in the Conceptual Model

You can create conceptual models in which foreign key columns in the database correspond to scalar properties on entity types. For more information, see Defining and Managing Relationships.

Self-Tracking Entities for N-Tier Application Development

You can now use the self-tracking entities when working with N-tier applications. The self-tracking entities can record changes to scalar, complex, and navigation properties. The tracking information in self-tracking objects could be applied to the object context on the service side. For more information, see Working with Self-Tracking Entities.

New Methods for N-Tier Application Development

New methods on classes in the System.Data.Objects namespace make it easier to develop N-Tier applications. For more information, see N-Tier Applications With Entity Framework.

EntityDataSource Support for the QueryExtender Control

The EntityDataSource control now supports the QueryExtender control, which is used to create filters for data retrieved from a data source. For more information, see Applying LINQ Queries to EntityDataSource.

Testability with IObjectSet<T>

The ObjectContext class now returns typed ObjectSet<TEntity> objects that you can use to perform create, read, update, and delete operations on entity objects. The ObjectSet<TEntity> class implements the IObjectSet<TEntity> interface. The IObjectSet<TEntity> interface may be useful in testing scenarios. For more information, see Working with ObjectSet.

Direct Execution of Store Commands

You can now directly execute store commands from the ObjectContext. For more information, see Directly Executing Store Commands.

Persistence-Ignorant Objects

You can use your own custom data classes together with your data model without making any modifications to the data classes themselves. This means that you can use "plain old" CLR objects (POCO), such as existing domain objects, with your Entity Framework application. For more information, see Persistence Ignorant Objects (Entity Framework).

With lazy loading, also known as deferred loading, related objects are automatically loaded from the data source when you access a navigation property. For more information, see Shaping Query Results (Entity Framework).

Functions in LINQ to Entities Queries

The EntityFunctions and SqlFunctions classes provide access to canonical and database functions from LINQ to Entities queries. The EdmFunctionAttribute allows a CLR method to serve as a proxy for a function defined in the conceptual model or storage model. For more information, see Calling Functions in LINQ to Entities Queries.

OrderBy Improvements in LINQ to Entities

LINQ to Entities queries that contain an OrderBy operator now return results ordered by the argument specified in the operator, regardless of the position of the operator in the query. However, the OrderBy operator in Entity SQL and ObjectQuery<T> queries is ignored if it is not the last operator in the query.

Customized Object-Layer Code Generation

You can configure the ADO.NET Entity Data Model Designer to use text templates to generate customized object-layer code. For more information, see How to: Customize Object-Layer Code Generation.

Model-First Support

The Generate Database Wizard enables you to do conceptual modeling first, and then create a database that supports the model. For more information, see How to: Generate a Database from a Conceptual Model.

Complex Type Support

The ADO.NET Entity Data Model Designer now supports complex types. For more information, see the following topics:

Naming Service

The Entity Data Model Wizard and the Update Model Wizard provide the option of using singular or plural forms of Entity, EntitySet, and NavigationProperty names to make application code more readable. For more information, see Choose Your Database Objects Dialog Box (Entity Data Model Wizard) and Choose Your Database Objects Dialog Box (Update Model Wizard).

Improved Model Browser Functionality

The Model Browser window of the ADO.NET Entity Data Model Designer enables you to delete objects from the storage model and to search the conceptual and storage models for a specified string. For more information, see Model Browser Window and How to: Delete Objects from the Storage Model.

Entity Designer Extensibility

You can extend the functionality of the ADO.NET Entity Data Model Tools by using classes in the Microsoft.Data.Entity.Design.Extensibility namespace to write Visual Studio extensions. Classes in the Microsoft.Data.Entity.Design.Extensibility namespace allow you to do the following:

  • Extend the .edmx file generation process.

  • Extend the .edmx file update process.

  • Add custom properties to objects in the Entity Designer and Model Browser.

  • Load and save custom file formats.

  • Extend the .edmx file loading and saving processes.

For more information, see Extending the Entity Data Model Tools.

Entity Data Model Documentation

The documentation for the Entity Data Model has been updated. For more information, see Entity Data Model.

See Also

Other Resources

ADO.NET

ADO.NET Overview

SQL Server and ADO.NET

What's New in WCF Data Services

ADO.NET Managed Providers and DataSet Developer Center