docs: private Scanner getScanner() throws HBaseException {
      final short metric_width = TSDB.metrics_width();
      final byte[] start_row = 
        Arrays.copyOfRange(Bytes.fromLong(start_id), 8 - metric_width, 8);
      final byte[] end_row = 
        Arrays.copyOfRange(Bytes.fromLong(end_id), 8 - metric_width, 8);
  
      LOG.debug("[" + thread_id + "] Start row: " + UniqueId.uidToString(start_row));
      LOG.debug("[" + thread_id + "] End row: " + UniqueId.uidToString(end_row));
      final Scanner scanner = tsdb.getClient().newScanner(tsdb.metaTable());
      scanner.setStartKey(start_row);
      scanner.setStopKey(end_row);
      scanner.setFamily("name".getBytes(CHARSET));
      scanner.setQualifier("ts_meta".getBytes(CHARSET));
      return scanner;
    }