public void TestConcreteRel()
{
ABA a = new ABA();
a.MyString = "a";
pm.MakePersistent(a);
ABB b = new ABB();
b.MyString = "b";
pm.MakePersistent(b);
pm.Save();
b.AddA(a);
pm.Save();
pm.UnloadCache();
b = (ABB)pm.FindObject(b.NDOObjectId);
Assert.AreEqual(1, b.MyA.Count, "Count wrong");
}