Setstufen richtig stellen

UPDATE d_anbupos SET upo_menge_sethauptpos=anp_menge
from D_ANBUPOS
inner join d_anbpos on anp_setnummer=upo_nummer
WHERE upo_setstufe<2

DECLARE @l_Stufe int;
SET @l_Stufe = 2;
WHILE @l_Stufe < 10
BEGIN
update S
   SET upo_menge_sethauptpos=H.UPO_MENGE*H.UPO_MENGE_SETHAUPTPOS
  from D_ANBUPOS S
 inner join D_ANBUPOS H on H.upo_seq=S.upo_setnummer
 where S.upo_setstufe=@l_Stufe
   AND S.upo_menge_sethauptpos<>H.UPO_MENGE*H.upo_menge_sethauptpos
 SET @l_Stufe = @l_Stufe + 1;
END