text: --  @testpoint:opengauss关键字defined(非保留)，自定义数据类型名为defined
  --关键字defined作为数据类型不带引号，创建成功
  drop type if exists defined;
  CREATE TYPE defined AS (f1 int, f2 text);
  select typname from pg_type where typname ='defined';
  drop type defined;
  
  
  --关键字defined作为数据类型加双引号，创建成功
  drop type if exists "defined";
  CREATE TYPE "defined" AS (f1 int, f2 text);
  select typname from pg_type where typname ='defined';
  drop type "defined";
  
  --关键字defined作为数据类型加单引号，合理报错
  drop type if exists 'defined';
  CREATE TYPE 'defined' AS (f1 int, f2 text);
  
  
  --关键字defined作为数据类型加反引号，合理报错
  drop type if exists `defined`;
  CREATE TYPE `defined` AS (f1 int, f2 text);
  