TechEd North America – Sessions Online Now!

If you missed out on all the festivities at TechEd North America in New Orleans last week, be sure to check out and catch the talks online.  All week long there was a ton of excitement about the new features in Entity Framework 4.0 and WCF Data Services/OData and lots of great questions.  Here’s… Read more

Improvements to Generated SQL in .NET 4.0

The information in this post is out of date. Visit for the latest information on current and past releases of EF. In a previous post (, we talked about the improvements to the quality and the readability of the SQL generated when querying using the Entity Framework that we made in .NET 4.0 Beta… Read more

ADO.NET Entity Framework Performance Comparison

There have been a few questions from the last performance blog post about how the Entity Framework compares against other object relational mapping frameworks. The simplest way to compare the performance of Entity Framework with various competing products is to use query performance against SqlClient as a benchmark. This way, anyone can run the same… Read more

Exploring the Performance of the ADO.NET Entity Framework – Part 2

Query Performance During this post I’ll show a few patterns on how to improve the query performance. A major design element for performance is the query cache. Once a query is executed, parts of the query are maintained in a global cache. Because of query and metadata caching, the second run always completes faster than… Read more

Exploring the Performance of the ADO.NET Entity Framework – Part 1

Performance Matters No matter what type of application you are developing at some point in the lifecycle of a software application or service, performance matters; this is especially true when accessing data. In this article, I’m going to spend some time exploring the performance of the ADO.NET Entity Framework by breaking down the stack and… Read more

ADO.NET performance improvements with the .NET Framework 2.0 SP1

With the release of Visual Studio 2008 and the .NET Framework 2.0 SP1, there are some bug fixes and improvements in ADO.NET (A list of the general fixes is at We worked with the CLR team to get improvements like the thread pool improved scalability, and that was important for making sure our SqlReader… Read more

ADO.NET Entity Framework Beta 3 Released!

Announcing the release of the ADO.NET Entity Framework Beta 3!   The  ADO.NET Entity Framework Beta 3 release enables users to visually design models and mappings using Visual Studio 2008 RTM and the .NET Framework 3.5 RTM. This release also incorporates fixes to bugs, performance improvements and includes many features requested by customers.   New features for… Read more

LOB Performance in SqlDataReader.

I’ve been answering a few questions here and there about performance for pulling LOB data out of a SqlDataReader and figured a discussion of what’s going on behind the scenes may be useful. This analysis is based primarily on the number of copies and movements of data, as well as a bit of code path… Read more