presto-parser/src/main/java/io/prestosql/sql/ReservedIdentifiers.java/ReservedIdentifiers/sqlKeywords
class ReservedIdentifiers:    public static Set<String> sqlKeywords()
    {
        ImmutableSet.Builder<String> names = ImmutableSet.builder();
        Vocabulary vocabulary = SqlBaseLexer.VOCABULARY;
        for (int i = 0; i <= vocabulary.getMaxTokenType(); i++) {
            String name = nullToEmpty(vocabulary.getLiteralName(i));
            Matcher matcher = IDENTIFIER.matcher(name);
            if (matcher.matches()) {
                names.add(matcher.group(1));
            }
        }
        return names.build();
    }