LINQ to SQL

LINQ to SQL is a component of .NET Framework version 3.5 that provides a run-time infrastructure for managing relational data as objects.

In LINQ to SQL, the data model of a relational database is mapped to an object model expressed in the programming language of the developer. When the application runs, LINQ to SQL translates into SQL the language-integrated queries in the object model and sends them to the database for execution. When the database returns the results, LINQ to SQL translates them back to objects that you can work with in your own programming language.

By using LINQ to SQL, you can use the LINQ technology to access SQL databases just as you would access an in-memory collection.

For example, the nw object in the following code is created to represent the Northwind database, the Customers table is targeted, the rows are filtered for Customers from London, and a string for CompanyName is selected for retrieval.

When the loop is executed, the collection of CompanyName values is retrieved.