sql - whats wrong with mysql tigger -

this trigger im trying add. keep getting "updating of new row not allowed in after trigger"

delimiter $$  drop trigger if exists leaderboard.badges_aupd$$ use leaderboard$$ create trigger `badges_aupd` after update on `badges` each row  set new.badgelevel := case when badgepercent < 50 0                     when badgepercent < 75 1                     else 2 end;     $$ delimiter ; 

your trigger should before update since after update cant set column of same table, , missing begin part

delimiter $$ drop trigger if exists leaderboard.badges_aupd$$ use leaderboard$$ create trigger `badges_aupd` before update on `badges`  each row begin  if new.badgepercent < 50    set new.badgelevel = 0 ;  elseif new.badgepercent < 75    set new.badgelevel = 1 ;  else     set new.badgelevel = 2;  end if;  end;$$  delimiter ;