presto-main/src/main/java/io/prestosql/sql/planner/optimizations/StreamPropertyDerivations.java/StreamPropertyDerivations/visitStatisticsWriterNode
class StreamPropertyDerivations:        @Override
        public StreamProperties visitStatisticsWriterNode(StatisticsWriterNode node, List<StreamProperties> inputProperties)
        {
            StreamProperties properties = Iterables.getOnlyElement(inputProperties);
            // analyze finish only outputs row count
            return properties.withUnspecifiedPartitioning();
        }