text: --  @testpoint:创建函数指定参数STABLE
  drop FUNCTION if exists func_add_sql006;
  CREATE FUNCTION func_add_sql006(integer, integer) RETURNS integer
      AS 'select $1 + $2;'
      LANGUAGE SQL
      STABLE
      RETURNS NULL ON NULL INPUT;
  /
  
  call func_add_sql006(999,1);
  drop FUNCTION func_add_sql006;