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