presto-parser/src/main/java/io/prestosql/sql/SqlFormatter.java/Formatter/visitDropTable
class Formatter:        @Override
        protected Void visitDropTable(DropTable node, Integer context)
        {
            builder.append("DROP TABLE ");
            if (node.isExists()) {
                builder.append("IF EXISTS ");
            }
            builder.append(node.getTableName());

            return null;
        }