title: Nhibernate - lock DB
body: <p>I'm using Nhibernate for the first time and I 've noticed that when I call BeginTransaction method it lock my Database.
  Instead, entity framework (ObjectContext or DbContext too) keeps all changes in memory and SaveChange method work perfectly if no error occurs without lock anything on db.</p>
  
  <p>Has Nhibernate some feautres like EF?</p>