Professional C# 4 and .NET 4

Chapter 56. LINQ to SQL

WHAT'S IN THIS CHAPTER?

• Working with LINQ to SQL using Visual Studio 2010

• Mapping LINQ to SQL objects to database entities

• Building LINQ to SQL operations without the O/R Designer

• Using the O/R Designer with custom objects

• Querying the SQL Server database using LINQ

• Stored procedures and LINQ to SQL

You will probably find the .NET Language Integrated Query Framework (LINQ) in C# 2010 to be one of the more exciting features the language has to offer. Basically, what LINQ provides is a lightweight façade over programmatic data integration. This is such a big deal because data is king.

Pretty much every application deals with data in some manner, whether that data comes from memory (in-memory data), databases, XML files, text files, or something else. Many developers find it very difficult to move from the strongly typed object-oriented world of C# to the data tier where objects are second-class citizens. The transition from one world to the next was a kludge at best and was full of error-prone actions.

In C#, programming with objects means a wonderful, strongly typed ability to work with code. You can navigate very easily through the namespaces, work with a debugger in the Visual Studio IDE, and more. However, when you have to access data, you will notice that things are dramatically different.

You end up in a world that is not strongly typed, where debugging is a pain or even non-existent, and you end up spending most of the time sending strings to the database as commands. ...