I have been recommended to use Entity Framework (EF) instead of LINQ to SQL while building .NET applications. So I pulled out some reference materials, learned the beginning concepts of EF, and started to build an application.
Then I started trying to figure out how to do Unit Testing and Test Driven Development (TDD) while using EF. What I had read about EF showed me how to build a SQL Server database and then have Visual Studio build the entities for me. I had to design the entire database first and then leave all the classes tied to the database, both of which are incompatible with TDD and Unit Testing.
So I started my Google search, and these are the documents I found really helpful. In the end, Unit Testing and TDD are compatible with EF! Here is where my journey took me:
TDD and ADO.NET Entity Framework
This late 2008 posting has several people sharing their concerns about using TDD with EF, which is where I was yesterday morning.
Walkthrough: POCO Template for the Entity Framework
Feature CTP Walkthrough: POCO Templates for the Entity Framework
These articles shows how to use the ADO.NET C# POCO Entity Generator and the Microsoft ADO.NET Entity Framework Feature Community Technology Preview 3 assembly to separate a .edmx Entity Framework file into two groups of classes: the persistence ignorant entity classes (not connected to the database), and the data context class which talks with the database.