presto-main/src/main/java/io/prestosql/sql/planner/iterative/rule/TransformCorrelatedSingleRowSubqueryToProject.java/TransformCorrelatedSingleRowSubqueryToProject/isSingleRowValuesWithNoColumns
class TransformCorrelatedSingleRowSubqueryToProject:    private static boolean isSingleRowValuesWithNoColumns(ValuesNode values)
    {
        return values.getRows().size() == 1 && values.getRows().get(0).size() == 0;
    }