presto-main/src/main/java/io/prestosql/sql/analyzer/StatementAnalyzer.java/Visitor/validateProperties
class Visitor:        private void validateProperties(List<Property> properties, Optional<Scope> scope)
        {
            Set<String> propertyNames = new HashSet<>();
            for (Property property : properties) {
                if (!propertyNames.add(property.getName().getValue())) {
                    throw semanticException(DUPLICATE_PROPERTY, property, "Duplicate property: %s", property.getName().getValue());
                }
            }
            for (Property property : properties) {
                process(property, scope);
            }
        }