LINQ to SQL introduces LINQ functionality for Microsoft SQL Server 2000 and 2005. Thanks to the IQueryable<T> interface, it's theoretically possible to create providers for other databases. Although it's not in the scope of this book, see articles from Matt Warren at his blog site for more information: http://blogs.msdn.com/mattwar/default.aspx.
LINQ to SQL defines new C# attributes, properties, and classes to let us interact with SQL Server databases by mapping database objects to objects in our programs. Three basic steps are required:
Create classes for the tables in the database that you want to use, decorating them with appropriate LINQ attributes. These classes are usually called entities.
Decorate the fields and ...