new ObjectIdQuery(new ObjectId("MtTable4", "ID", 1)));
assertEquals(2, o1.getTable5s().size());
assertEquals(2, o2.getTable5s().size());
ClientMtTable5 o1r = (ClientMtTable5) Cayenne.objectForQuery(
c1,
new ObjectIdQuery(new ObjectId("MtTable5", "ID", 1)));
o1.removeFromTable5s(o1r);
c1.commitChanges();