select 	T.materialCode, 
		b.materialName, 
		b.dimension, 
		dbo.uf_unitName(b.unitCode) unitName, 
		sum(T.materialQty) materialQty, 
		sum(T.buyingAmt) buyingAmt, 
		sum(T.buyingVat) buyingVat, 
		b.domesticText 
	from  
	(select 
		a.dealerCode, 
		a.materialCode ,
		sum(isNull(a.materialQty,0))-sum(isNull(a.rtnQty,0)) materialQty, 
		sum(isNull(a.buyingAmt,0)) buyingAmt, 
		sum(isNull(a.buyingVat,0)) buyingVat 

	from orders a 
	where a.dealerCode='1001' 
	and a.stockInDay between '20200425' and '20200425' 
	and a.storeCode='2100' 
	group by a.dealerCode,a.materialCode) T,material b 
	where T.dealercode=b.dealerCode 
	and T.materialCode=b.materialCode 
	group by rollup((T.materialCode, b.materialname, b.dimension, b.unitcode, b.domesticText))
	order by T.materialCode

를 통해 사진에 null을 총계로바꾸고싶은데 어떻게해야하나요?