CREATE FUNCTION `getPicturesCount`(aID bigint) RETURNS bigint( 20 )
return (select sum(isgroup= 3 ) + sum(getPicturesCount(id)) from foto_foto where top = aID);

drop procedure if exists go;
drop function if exists calc;

delimiter |

create procedure go(p_id int, p_isgroup int, in k1 int, out k2 int)
begin
  declare done, l_id, l_isgroup int default  0 ;
  declare cur cursor for 
    select
      id,
      isgroup
    from
      foto_foto
    where
      top = p_id;
  declare continue handler for sqlstate '02000' set done =  1 ;

  set k2 = k1;
  open cur;
    repeat
      fetch cur into l_id, l_isgroup;
      if not done then
        call go(l_id, p_isgroup, k2 + if(l_isgroup = p_isgroup,  1 ,  0 ), k2);
      end if;
    until done end repeat;
  close cur;
end
|

create function calc(p_id int, p_isgroup int) returns int
begin
  declare k int default  0 ;
  call go(p_id, p_isgroup, k, k);
  return k;
end

select calc( 1 ,  3 )