Summary
In this chapter, we have learned what an ORM is, why we need an ORM, and what LINQ to Entities is. We also compared LINQ to SQL with LINQ to Entities and explored some basic features of LINQ to Entities.
The key points covered in this chapter include:
An ORM product can greatly ease data access layer development
LINQ to Entities is one of Microsoft's ORM products that uses LINQ against a .NET Conceptual Entity Model
The built-in LINQ to Entities designer in Visual Studio 2010 can be used to model the Conceptual Entity Model
You can generate the Conceptual Entity Model from a physical database in the Visual Studio 2010 Entity Model designer
The class,
System.Data.Objects.ObjectContext, is the main class for LINQ to Entities applicationsLINQ methods that return a sequence defer the query execution and you can check the timing of the execution of a query with Profiler
LINQ query expressions that return a singleton value will be executed as soon as they are defined
By default the loading of...
