Pre-Generating Views in Entity Framework .NET 4.0

 

UPDATED ON: 16/09/2010

If you’re using Entity Framework chances are you’ve come up against performance issues already, especially when instantiating your Object Context.

One very reliable way to increase performance is to pre-generate the Views. Depending on the size of your model and in my experience it can shave as much as 40% off the instantiation time.

There is a good overview on MSDN, however it only covers .NET 3.5.

Step 1

Go to your Model properties and select “Copy to Output Directory” for the Metadata Artifact Processing option.

The result of this is you will end up with the .ssdl, .csdl and .msl files in your output directory which in this case is bin/Debug.

Step 2

Next you need to setup the Pre-build event to use the EDMGen.exe tool.
NB: If you use the Command on the MSDN site you will come across this error.

“The required parameter ‘mode’ is missing”

The correct command to use is:

"%windir%\Microsoft.NET\Framework\v4.0.30319\EdmGen.exe" /mode:ViewGeneration "/inssdl:$(TargetDir)MyModel.ssdl" "/incsdl:$(TargetDir)MyModel.csdl" "/inmsl:$(TargetDir)MyModel.msl" "/outviews:$(ProjectDir)MyModel.Views.cs" /nologo /language:CSharp

 

Step 3

The .ssdl, .csdl & .msl files will be generated on every build and output to the TargetDir, however it’s a good idea to include them in your Project.

In the Post-build event you can add a simple XCOPY like below to copy the files to the root of your project:

XCOPY "$(TargetDir)MyModel.csdl" "$(ProjectDir)" /R /Y
XCOPY "$(TargetDir)MyModel.ssdl" "$(ProjectDir)" /R /Y
XCOPY "$(TargetDir)MyModel.msl" "$(ProjectDir)" /R /Y

 

Step 4

Build the project which contains your Entity Model.

If it built successfully you should find the following files in the root of your Project folder

• MyModel.Views.cs
• MyModel.csdl
• MyModel.ssdl
• MyModel.msl

Go ahead and include all these files in your project, Show All Files > Right Click > Include In Project

Step 5

Now for MyModel.csl, MyModel.ssdl, MyModel.msl you want to include these as an embedded resource

For each of the above files select the “Embedded Resource” Build Action in the Properties window.

Step 6

Now it’s time to update your Entity Connection String to use the embedded resources.

Personally I prefer to use fully qualified names for the embedded resources.

e.g.

res://*/MyNamespace.MyModel.MyModel.csdl 

You should end up with a Connection String looking like below. 

<connectionStrings>
    <add name="MyModel_Entities" connectionString="metadata=res://*/MyNamespace.MyModel.MyModel.csdl|res://*/MyNamespace.MyModel.MyModel.ssdl|res://*/MyNamespace.MyModel.MyModel.msl;provider=System.Data.SqlClient;provider connection string=&quot;Data Source=local;Initial Catalog=MyModelDatabase;Integrated Security=True;MultipleActiveResultSets=True&quot;" providerName="System.Data.EntityClient" />
  </connectionStrings>

If the path to the embedded resource is wrong you can expect to get a System.Data.MetadataException

Unable to load the specified metadata resource.

To be sure what the Resource path is, you can always use the trusty Reflector.

Finished

Enjoy your new found Entity Framework performance.
If you have any problems, don’t hesitate to let me know.