final byte[] tagk = { 't', 'a', 'g', 'k' };
final byte[] tagv = { 't', 'a', 'g', 'v' };
kvs.add(new KeyValue(MAXID, ID, metrics, Bytes.fromLong(64L)));
kvs.add(new KeyValue(MAXID, ID, tagk, Bytes.fromLong(42L)));
kvs.add(new KeyValue(MAXID, ID, tagv, Bytes.fromLong(1024L)));
final TSDB tsdb = mock(TSDB.class);
when(tsdb.getClient()).thenReturn(client);
when(tsdb.uidTable()).thenReturn(new byte[] { 'u', 'i', 'd' });
when(client.get(anyGet()))
.thenReturn(Deferred.fromResult(kvs));
final byte[][] kinds = { metrics, tagk, tagv };
final Map<String, Long> uids = UniqueId.getUsedUIDs(tsdb, kinds)