现有记录:
OrderNo ProductID Quantity1 1 501 2 301 3 202 2 303 1 1003 4 504 1 204 5 105 2 10
预期产出
ProductID Quantity1 1702 704 50
SELECT TOP 3 ProductID,SUM(Quantity) as qSumFROM TableGROUP BY ProductIDORDER BY qSum DESC