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