Oracle SQL MODEL: Using analytic clauses

create table tq84_model_analytic(
   id   integer primary key,
   txt  varchar2(10)
);
 
begin
   insert into tq84_model_analytic values (1, 'one'  );
   insert into tq84_model_analytic values (2, 'two'  );
   insert into tq84_model_analytic values (3, 'three');
   insert into tq84_model_analytic values (6, 'six'  );
   insert into tq84_model_analytic values (9, 'nine' );
   commit;
end;
/
 
select
   *
from
   tq84_model_analytic
model
   dimension by (
      id
   )
   measures (
      txt,
      cast(null as number(4)      )  pos,
      cast(null as varchar2(20)   )  prev_txt
   )
   rules (
     pos     [any] = row_number(   ) over (order by id),
     prev_txt[any] = lag       (txt) over (order by id)
   );
--
--         ID TXT               POS PREV_TXT           
-- ---------- ---------- ---------- --------------------
--          1 one                 1                    
--          2 two                 2 one                
--          3 three               3 two                
--          6 six                 4 three              
--          9 nine                5 six