Thank you Patato
i think there is wrong small things , its easy for anyone know well in sql but there who dont know how to fix it so i try to share it for them but its not my query guys its Patato one
Declare @

float = 1.0;
UPDATE dbo.Tab_RefNest
SET dwmaxtotalcount = CASE WHEN CONVERT(INT,ROUND(dwmaxtotalcount @

,0)) = 0 THEN 1 ELSE CONVERT(INT,ROUND(dwmaxtotalcount @

,0)) END
FROM Tab_RefNest as tabrn
JOIN Tab_RefTactics as tabrt on tabrn.dwTacticsID = tabrt.dwTacticsID
JOIN _RefObjCommon as ref on tabrt.dwObjID = ref.ID
WHERE
TypeID1 = 1 AND TypeID2 = 2 AND TypeID3 = 1 AND Rarity = 3 AND [Service] = 1