Thursday, April 1, 2010

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.

ef-pre-generate

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.

13 comments:

  1. Very helpful. You helped answer something that I was stuck on and posted about on Stackoverflow:
    http://stackoverflow.com/questions/4214449/pre-generated-entity-framework-views-in-azure/4232489#4232489.
    Thanks.

    ReplyDelete
  2. While Building project I got this error.
    Error 6 The path 'D:\TCMS PERFORMANCE\SourceCodeI3\TCMS.Server\bin\Debug\TCMSDataModel.ssdl' given for the argument 'inssdl' is not a valid file or directory. D:\TCMS PERFORMANCE\SourceCodeI3\TCMS.Server\EXEC TCMS.Server

    Could you please tell me Why did I get this one?

    ReplyDelete
  3. Thanks, really clear and concise blogging!

    ReplyDelete
  4. Very clear, nice post.

    ReplyDelete
  5. You may also get the “The required parameter ‘mode’ is missing” error if you copy and pasted the command because there shouldn't be any hard return placing the /mode on the next line.  In other words, if you get this error, look at the pre-build command line in the project properties, and the command should be all on one line.  If it is on multiple lines then you have copy/pasted hard returns with it and you need to delete the return at the end of the line and make sure the command is on one line.

    ReplyDelete
  6. Use T4.

    http://social.msdn.microsoft.com/Forums/en-US/adodotnetentityframework/thread/4e391552-f589-4605-99f9-0b67cd60a018

    ReplyDelete
  7. Interesting approach. But I prefer this to happen transparently at compile time.

    ReplyDelete
  8. After executing step 2, i am getting an error in cmd prompt "error 7001: failed to find or load the registered .Net Framework Data Provider". I am using ".NET Framework Data Provider for SQL Anywhere11".
    Can anybody tel me what can be the reason of this error?

    ReplyDelete
  9. You rock man...  My simple query cut down to less than 1 sec that prevously takes about 1-1.5 sec... It's a significant benefit when it comes to application-wide...

    ReplyDelete
  10. Nice post. Question: what tells the EF that there are pregenerated views?the file name? The conn string change just tells that the csdl and other files are embedded.

    ReplyDelete
  11. great article. Thank you.

    ReplyDelete