在MySQL中，为Products表选择适当的查询，其中的数据应主要按ProductGroup列升序显示。二级排序应按CurrentStock列的降序排序。( )
Select * from Products order by CurrentStock,ProductGroup
Select * from Products order by CurrentStock DESC,ProductGroup
Select * from Products order by ProductGroup,CurrentStock
Select * from Products order by ProductGroup,CurrentStock DESC
都不对
