presto-raptor-legacy/src/main/java/io/prestosql/plugin/raptor/legacy/RaptorMetadata.java/RaptorMetadata/getPartitioningHandle
class RaptorMetadata:    private RaptorPartitioningHandle getPartitioningHandle(long distributionId)
    {
        return new RaptorPartitioningHandle(distributionId, shardManager.getBucketAssignments(distributionId));
    }