Migrating a Windows Forms Application with SQL Server back end to Silverlight

Question

Presently I have a Windows Forms application that obtains data from a SQL Server database on a separate server in our LAN. Basically we want to re-use as much as possible our source code that interacts with the SQL Server database and change the forms portion to a thin client silverlight solution. The problem is that our Windows Forms application is a fat client application; however, our company recently added employees working several thousand miles away, so they have a long delay in working with our application as it retrieves data from the database server which is a long ways away from the employee's client forms application.

The ideal solution for me would allow the developer to display data based on various database tables or views dynamically at runtime say based on what treeview item a user clicks and not having to hard code the database schema at design time. This is the way our windows forms application presently works.

One aspect of silverlight I am wrestling with right now is that if you want to access data from a SQL Server database on the web server side you have to use web services or WCF RIA, which of course involves creating a design time EDMX file or generating LINQ to SQL classes. The problem is that our database schema changes quite frequently, so that means I would have to keep manually re-updating the web services along with the EDMX and/or LINQ to SQL. What I would really like to do would be to just connect to the SQL Server database using ADO.NET to populate the various silverlight datagrids without having to deal with web services. Please note that I am pretty new to Silverlight, so perhaps I am missing something obvious.

Here is one of the many links I have checked as I've been working on this solution; however, this just migrates a Windows Forms application that already has a web service to a silverlight application that has a similar web service, so it doesn't seem to apply to my situation:

http://www.silverlight.net/learn/advanced-techniques/moving-from-windows-forms/migrating-a-windows-forms-application-to-silverlight

Here is another website that I have been looking at closely; however, the database that I am working with is so huge and has such a large schema that whenever I attempt to open or work with the Data->Show Data Sources or Data->Add Data Source window in Visual Studio it takes about an hour of the CPU running at full throttle before it displays the values in visual studio. Of course this makes Visual Studio almost unusable if this hour long wait happens every time I try to make a change in the silverlight XAML designer:

http://msdn.microsoft.com/en-us/gg315272

Also, the website example above is not an acceptable solution because we want the web server and the database server to be two separate machines, so we would not be able to put the database into the App_Data folder in the silverlight solution.

If anyone has any suggestions or guidance in terms of migrating this application, they would be most appreciated. TIA.

Roger

Answer 1

Basically I found out that since I'm used to writing desktop applications that communicate directly with a database (such as SQL Server), I was surprised to find that there is no object in Silverlight to enable you to do (SqlConnection, OdbcConnection, etc.). This is because Silverlight is a client platform, designed to be run from within a browser anywhere in the world, and so it does not make sense for it to be able to access databases directly because databases are generally hidden behind a firewall. The purpose of a service is to provide an interface for exposing data publicly from the server, acting as a conduit between the data in the database and external applications. (source: "Pro Business Applications with Silverlight 5" by Chris Anderson)

Please note that I also had made a mistake when I created a DomainService and assigned to it all the tables, queries, and stored procedures in the entire database, when in fact one needs to create a separate domain service for each individual table or query. This explains why I had the problem before where I had to wait about an hour for the Data Sources window to populate.