text: -- @testpoint: 模式匹配操作符SIMILAR TO,使用元字符*，重复项为多个字符
  DROP TABLE IF EXISTS type_char;
  CREATE TABLE type_char (string1 varchar(10));
  insert into type_char values ('abcd');
  SELECT  * from type_char  where string1 SIMILAR TO '(ab)*cd';
  DROP TABLE IF EXISTS type_char;