Programming C# 4.0, 6th Edition

Chapter 14. Databases

Databases are one of computing’s most important inventions. They allow applications to store massive quantities of information, with the ability to search through millions of items and retrieve the ones you need in a fraction of a second. A high-quality database can scale to large numbers of concurrent end users, while providing very reliable storage, even in the face of system crashes. And even if you don’t need the scalability, databases still look compelling if your program needs to remember data for any length of time—applications that store valuable information usually rely on databases.

The .NET Framework provides several different ways to communicate with databases. We will mainly be looking at its most recently introduced data access mechanism, the Entity Framework, and how that works with the LINQ features of C#. But first, we’ll take a quick look at all of the database features of the .NET Framework, to put the Entity Framework in context.

The .NET Data Access Landscape

The main focus of this chapter, the Entity Framework, was first released as part of Service Pack 1 for Visual Studio 2008, which emerged less than a year after the initial (pre-Service-Pack) release of Visual Studio 2008. This was remarkable, since that first release had already introduced a brand-new data access feature, LINQ to SQL, but then Microsoft has released a lot of data access technologies over the years.

While the pace of change can sometimes seem daunting, each new piece has ...