presto-main/src/main/java/io/prestosql/sql/planner/optimizations/AddExchanges.java/AddExchanges/visitUnnest
class AddExchanges:        @Override
        public PlanWithProperties visitUnnest(UnnestNode node, PreferredProperties preferredProperties)
        {
            PreferredProperties translatedPreferred = preferredProperties.translate(symbol -> node.getReplicateSymbols().contains(symbol) ? Optional.of(symbol) : Optional.empty());

            return rebaseAndDeriveProperties(node, planChild(node, translatedPreferred));
        }