Lightswitch is slow, ADO.NET Entity Framework/Doma

Question

I'm developing an Lighswitch application in VS2012 with an external SQL Server 2008. I'm using a WCF RIA Service to fetch my data, using these techniques: http://www.c-sharpcorner.com/UploadFile/raj1979/how-to-use-wcf-ria-service-in-lightswitch-2012/.

My main table contains some columns with static data and about 5 columns with foreign keys. The static data columns loads instant but all the foreign properties takes 3-5 secs to load on a screen with ~100 rows. This is not acceptable..

The problem for me is that I don't know where the bottleneck might be. Any ideas where I could start looking? The only thing I could think of so far is that my ADO.NET model uses Lazy Loading, and it does.

All the foreign key properties only has two columns with a PK and some text, so they're not data heavy.

Any help appreciated, thanks!

Answer 1

I am almost a beginer at this new art, but as Yan says in his book, instead a very good one, lightswitch is directed to the screen. I dare to ask you if you need to have 100 lines in your screen. You can't even see them all. If you reduce that number to 20 you will reduce your waiting time to 1/5th. I've had the same problem and now I use the least possible number of rows in screen. For that to be possible without disturbing the business performance, I choose to open screens with the maximum number of parameters, not required, which I send when I open them. If one of the parameters is not the option in the case I mention it as "Nothing". And so, I can have a minimum number of lines in the grid, fullfiling the purpous of teh screen, the program performance and the business performance.

Answer 2

I don't know if this is the exact answer to your speed problem, but that article you quoted suggests that you add a new ADO.NET Data Model to the class library containing the RIA Service.

There's absolutely no reason to generate a second data model, as LightSwitch already generates one when you attach the external data source (your SQL Server database). You may as well re-use it. An EF data model takes time to construct, so I suppose that using two EF data models could explain the slowness you're experiencing, but it could also be something else entirely.

Have a look at this article (the original RIA Service/LightSwitch article, & still the best), which among several other techniques, Eric will show you how to re-use the data model that LightSwitch creates for your data source.

How Do I: Display a Chart Built On Aggregated Data

In this article, the RIA service is created to specifically aggregate data to display in a chart, but you can do whatever you need to do in it. It doesn't have to aggregate data. I use RIA services with an attached data source (a SQL database) extensively, to provide data for lists, reports, as well as lookup data for combo boxes.