Microsoft SQL

Could you recommend to me good books and manuals on how to learn Microsoft SQL?

Don't use an object-relation mapper. These things don't make sense at all. The mapping between (objects, inheritance, embedded objects) and (tables,relations) is ill defined. For some constructs, there is no rational general mapping. A group by statement is difficult to model and requires the programmer to create a new object.

Some ORM's do their joins in memory. This hampers the performance of the application.

ORM are only good for the trivial cases.

Instead of this implement a small relational algebra. It is not difficult and still saves you time, but you remain in full control.