text: --[er]Test delete on superclass with only and except keyword
  
  create class t1 (name varchar(20), age integer);
  create class sub_t1 as subclass of t1(gender char(1));
  
  insert into t1 values('Jerry', 25);
  insert into t1 values('Tom', 26);
  insert into t1 values('Kitty', 27);
  insert into t1 values('Cat', 23);
  
  
  insert into sub_t1 values('Sun', 26, 'f');
  insert into sub_t1 values('Moon', 27, 'm');
  insert into sub_t1 values('Star', 22, 'f');
  insert into sub_t1 values('Jerry', 21, 'f');
  
  delete from only t1 (except sub_t1) where name = 'Jerry';
  select * from t1 order by 1;
  
  select * from sub_t1 order by 1;
  
  drop class t1;
  drop class sub_t1;
  