public void getSubRecordsBetween(MultiResultSet results, Long from, Long to) {
   Set<Long> values = sortedSet.subSet(from, to);
   for (Long value : values) {
     ConcurrentMap<Long, Record> records = mapRecords.get(value);
     if (records != null) {
       results.addResultSet(value, records.values());
     }
   }
   // to wasn't included so include now
   ConcurrentMap<Long, Record> records = mapRecords.get(to);
   if (records != null) {
     results.addResultSet(to, records.values());
   }
 }