.NET 4 ships with a much improved version of Entity Framework (EF) – a data access library that lives in the System.Data.Entity namespaceWhen Entity Framework was first introduced with .NET 3.5 SP1, developers provided a lot of feedback on things they thought were incomplete with that first release. The SQL team did a good job of listening to this feedback, and really focused the EF that ships with .NET 4 on addressing it. Some of the big improvements in EF4 include: POCO Support: You can now define entities without requiring base classes or data persistence attributes.
Lazy Loading Support: You can now load sub-objects of a model on demand instead of loading them up frontN-Tier Support and Self-Tracking Entities: Handle scenarios...(
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