Question: Hey all, I have a linq app using C# express2008 and sqlserver express 2005 (mdf file connection)
I followed the regular dml generation and vanilla datacontext. However i created a repository class to manage the Linq stuff. 
In using the functions, selecting data works fine, updating data works in the app.But when i check the data in the tables, nothing has changed.Needless to say, when i close the app, also no change.
I used SQL profiler to see what was being sent to sqlserver express, nothing showed up.

What could be my issues?

Answer: 
Are you calling SubmitChanges() on the DataContext?
No primary key, or no column(s) in the L2S model marked as primary key member(s)..?