presto-raptor-legacy/src/main/java/io/prestosql/plugin/raptor/legacy/metadata/DatabaseShardManager.java/DatabaseShardManager/getShardNodesBucketed
class DatabaseShardManager:    @Override
    public ResultIterator<BucketShards> getShardNodesBucketed(long tableId, boolean merged, List<String> bucketToNode, TupleDomain<RaptorColumnHandle> effectivePredicate)
    {
        return new ShardIterator(tableId, merged, Optional.of(bucketToNode), effectivePredicate, dbi);
    }