presto-spi/src/main/java/io/prestosql/spi/type/RowType.java/RowType/getDisplayName
class RowType:    @Override
    public String getDisplayName()
    {
        // Convert to standard sql name
        StringBuilder result = new StringBuilder();
        result.append(ROW).append('(');
        for (Field field : fields) {
            String typeDisplayName = field.getType().getDisplayName();
            if (field.getName().isPresent()) {
                // TODO: names are already canonicalized, so they should be printed as delimited identifiers
                result.append(field.getName().get()).append(' ').append(typeDisplayName);
            }
            else {
                result.append(typeDisplayName);
            }
            result.append(", ");
        }
        result.setLength(result.length() - 2);
        result.append(')');
        return result.toString();
    }