presto-main/src/main/java/io/prestosql/sql/planner/optimizations/ActualProperties.java/Global/isEffectivelySingleStream
class Global:        private boolean isEffectivelySingleStream(Set<Symbol> constants)
        {
            return streamPartitioning.isPresent() && streamPartitioning.get().isEffectivelySinglePartition(constants) && !nullsAndAnyReplicated;
        }