Entity Framework
The Entity Framework is a set of technologies in ADO.NET that helps fill in the space between object-oriented development (objects) and databases. This gap is commonly known as an “impedance mismatch” and it exists because the mapping and organization of classes does not quite match up to the organization of relational objects. Many mapping solutions have tried to solve this problem by mapping OO (object-oriented) classes and properties straight to tables and columns.
常见的已有类似产品
• NHibernate: Ported from Hibernate Core for Java for the .NET Framework, NHibernate for .NET persists plain .NET objects to and from an underlying relational database.
• SPRINT.net: An open-source application framework, and based on the Java version of Spring Framework, allowing you to build components that can be integrated into multiple tiers of your application.
如何入手
EF是基于Linq，因此Linq要熟悉
对SQL server的基本使用要了解
两本看过的推荐图书：
Entity Framework 4.0 Recipes A Problem-Solution Approach
Pro Entity Framework 4.0
熟悉这些以后，就可以基本按照面向对象的方法处理数据层的对象和各种关系了，对于一些快速开发的中小项目可以完全的支持。
Entity FrameWorkd Tip on blog.msdn
http://www.cnblogs.com/xray2005/category/189491.html
最近在使用这个框架，感觉vs2010对这个功能增强的很多,特别是IDE的支持功能更强，显著提高开发效率，吸收了广泛的意见，结合看的书，把一些重点着几天整理记录一下以备参考。