Focusing on development of data-centric applications, Microsoft released on Thursday Beta 3 of the ADO.Net Entity Framework and plans to release shortly a preview of ASP.Net 3.5 Extensions.

ADO.Net Entity Framework is designed to make it easier to build data-centric applications and services regardless of the underlying data source, Microsoft said.

"This provides a new modeling framework that enables developers to define a conceptual model of a database schema that closely aligns to a real world view of the information," said Microsoft's Scott Guthrie, a general manager within the company's Developer Division, in his blog. "We will also be shipping a new set of data services, code-named 'Astoria,' that make it easy to expose REST-based API end points from within your ASP.Net applications."

Beta 3 supports the newly released Visual Studio 2008 development platform and .Net Framework 3.5. Also featured is easier disconnected operation, business logic enhancements, and query improvements.

ADO.Net Entity Framework has support from database and third-party companies. This support includes IBM, which will provide connectivity to DB2 and Informix databases; MySQL, supporting its MySQL database, and Sybase, which will link the Microsoft software to SQL Anywhere databases, Microsoft said. The new beta release is accessible here.

The framework extends Microsoft's LINQ (Language Integrated Query) technology by enabling developers to use LINQ against many back-end databases, according to the company. Developers can focus on business logic rather than data access, Microsoft said.

"[Entity Framework is] sort of another step in making databases easier for programmers," said Greg DeMichillie, lead analyst for Directions on Microsoft.

The way that databases have been set up, developers must cope with having different bits of information about a customer, for example, in different tables. The entity framework maps between the relational table where the data is stored and higher level entities programmers want to use, DeMichillie said.

ASP.Net 3.5 Extensions leverages Entity Framework for building rich, interactive data-centric applications on the Web. It provides a look at features planned for ASP.Net next year. ASP.Net enables development of Web sites.

The ASP.Net 3.5 Extensions Preview offers the following features:

-- ADO.Net Entity Framework.

-- ASP.Net AJAX improvements, offering better browser history support integration and server-side history management via a server control. Improved AJAX (Asynchronous JavaScript and XML) content-linking also is offered.

-- Silverlight controls, for integrating Silverlight, Microsoft's new multimedia applications platform, with ASP.Net server controls. These controls include one that integrates media sources such as Windows Media Video into a Web application, and another control for referencing custom XAML and associated JavaScript files.

-- ASP.Net Dynamic Data support, for building data-centric applications quickly.

-- ADO.Net Data Services, offering an infrastructure to enable Web applications to expose data as a service consumable by client applications in corporate networks and on the Internet.

--ASP.Net MVC (Model View Controller), extending MVC support to the ASP.Net 3.5 runtime so developers can more easily take advantage of this design pattern.

Microsoft has not set release dates yet for the general release versions of ADO.Net Entity Framework and ASP.Net Extensions 3.5.

Microsoft also said the next major version of Microsoft .Net Data Provider for DB2 will continue to be included as part of Host Integration capabilities in Microsoft BizTalk Server "6." With this integration, developers will be able to interact with DB2 database objects using the Entity Framework.