@Test
public void testCardinality() {

    L locator = getLocator();
    Record<L, K, V> record = getRecord(locator);
    Set<K> keys = Sets.newHashSet();
    for (int i = 0; i < TestData.getScaleCount(); ++i) {
        K key = getKey();
        V value = getValue();
        Revision<L, K, V> revision = getRevision(locator, key, value);
        record.append(revision);
        keys.add(key);
    }
    Assert.assertEquals(keys.size(), record.cardinality());
}