4、 ds2.[Sales]from(select[ProductCategory],[ProductSub-Category],SUM(Sales)asSalesfromOrdersgroupby[ProductCategory],[ProductSub-Category])ds1leftjoin (select[ProductCategory],SUM(Sales)asSalesfromOrdersgroupby[ProductCategory])ds2 on ds1.[ProductCategory]=ds2.[ProductCategory]4、将ds2中[Productsub-
6、rsgroupby[ProductCategory],[ProductSub-Category])ds1leftjoin (select[ProductCategory], casewhenmin([ProductSub-Category])=max([ProductSub-Category])themin([ProductSub-Category]) else"*"end as[ProductSub-Category] --重点在这行 SUM(Sales)asSalesfromOrdersgroupby[ProductCategory])ds2 on d