public void test3() { int i = 1; Foo foo = new Foo() { Name = "foo", Height = 1, DateTime = DateTime.Now }; Book book = new Book { Name = "a", Author = "a" }; using (ISession session = sqliteSessionFactory.Session) { using (ITransaction transaction = session.BeginTransaction()) { foo.AddBook(book); session.SaveOrUpdate(foo); transaction.Commit(); Assert.That(foo.Id > 0); } var foos = session.CreateCriteria(typeof(Foo)).List <Foo>(); Assert.That(foos.Count, Is.EqualTo(1)); Assert.That(foos[0].Books.Count, Is.EqualTo(1)); } }