drop table if exists test003;
create table test003 (id int, v char(1));
insert into test003 (id, v)
VALUES
(1,'z'),
(2,'a'),
(3,'b'),
(4,'c'),
(5,'d');

drop procedure if exists tmp_002;
create procedure tmp_002()
begin
declare done int default 1;
declare previd, currid int default 0;
declare prevV, currV char(1);
declare cur cursor for select id, v from test003 order by id desc;
declare continue handler for not found set done=0;
open cur;
fetch cur into currid, currV;
while done do
  if previd > 0 then 
    update test003 set v = prevV where id = currId; 
   else
    update test003 set v = '' where id = currId; 
  end if;
  set previd = currid;
  set prevV = currV;
  fetch cur into currid, currV;
end while;
close cur;
end;

call tmp_002();
select a.* from test003 a;