@Test
 public void findAllValuesOfAGivenAxis() {
   List<PdcAxisValue> values = dao.findByAxisId(2l);
   assertThat(values.size(), is(3));
   assertThat(values.get(0), is(aPdcAxisValue("4", "2")));
   assertThat(values.get(1), is(aPdcAxisValue("5", "2")));
   assertThat(values.get(2), is(aPdcAxisValue("6", "2")));
 }
 @Test
 public void findNoValuesOfAnUnknownAxis() {
   List<PdcAxisValue> values = dao.findByAxisId(1000l);
   assertThat(values.isEmpty(), is(true));
 }