I studied most of the book and I was evaluated by a couple of .NET experts in the end. The interview was successful and I officially started developing database applications in C#.

I try to update here as soon as I learn new techniques, tips and tricks. For now, I start with ” LINQ to SQL”.
LINQ to SQL is a kind of sophisticated OR Mapper (Object Relational Mapper) which has several useful features that results easier and simpler development.

This is what Microsoft experts say:
“LINQ to SQL provides a runtime infrastructure for managing relational data as objects without losing the ability to query. Your application is free to manipulate the objects while LINQ to SQL stays in the background tracking your changes automatically.”

For more information please visit:  http://msdn.microsoft.com/en-us/library/bb425822.aspx

P.S.
A friend of mine who showed me the capabilities of LINQ to SQL, also said that this technology is obsolete right now and “Entity Framework” should probably be replaced with it. Entity Framework version 1 was released with .NET framework 3.5 service pack 1 and the next version will be released by .NET framework 4.