Does Entity Framework's DbContext save changes if no changes were made?

Question

I could not find an answer on the Internet.

Let's suppose I have a DbContext , and I just select all the entities from it. I don't add, update or delete any entity on the DbSet .

If I call SaveChanges afterwards on the DbSet . Does it actually waste resources establishing a connection and other stuff even If I did not made any changes to the DbSet ?

Is it smart enough to detect if a change was made or not, and behave differently?

Answer 1

It uses EntityState to determine that there is nothing to commit and so does not waste resources.

http://msdn.microsoft.com/en-us/library/system.data.entitystate%28v=vs.110%29.aspx