LINQ-to-SQL has been a huge success with the .NET community. While other ORM frameworks such as nHibernate, SubSonic, etc...have been available for years, many Microsoft shops prefer to work with Microsoft offerings when available. For those nHibernate users out there, the visual designer for LINQ-to-SQL is also a welcome feature in Visual Studio--no more XML files to edit.

As most already know, LINQ-to-SQL is only for use with SQL Server and for projects with a near 1:1 relationship between the database schema and domain model. What if you want to use Oracle? What if your domain model differs from the underlying relational structure? LINQ-to-Entities addresses these concerns.

LINQ-to-Entities is the next major addition to ADO.NET, and it provides a much fuller feature set than LINQ-to-SQL such as:

• Domain Modeling Capabilities and the ability to define conceptual, data store agnostic models
• Object Relational Mapping Capabilities (full CRUD and state management scenarios)
• Database independent Query Capabilities using LINQ or Entity SQL