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Sql中Rank排名函数

A.对分区中的行进行排名

以下示例按照数量对指定清单位置的清单中的产品进行了排名。

 结果集按 LocationID 分区并在逻辑上按 Quantity 排序。

 注意,产品 494 和 495 具有相同的数量。 因为它们是关联的,所以两者均排名第一。

 
USE AdventureWorks2012;
GO
SELECT i.ProductID, p.Name, i.LocationID, i.Quantity ,
RANK() OVER (PARTITION BY i.LocationID ORDER BY i.Quantity DESC) AS Rank FROM Production.ProductInventory AS i INNER JOIN Production.Product AS p ON i.ProductID = p.ProductID WHERE i.LocationID BETWEEN 3 AND 4 ORDER BY i.LocationID; GO

下面是结果集:

 
 
ProductID   Name                   LocationID   Quantity Rank
----------- ---------------------- ------------ -------- ----
494         Paint - Silver                3            49       1
495         Paint - Blue                  3            49       1
493         Paint - Red                   3            41       3
496         Paint - Yellow              3            30       4
492         Paint - Black                 3            17       5
495         Paint - Blue                  4            35       1
496         Paint - Yellow              4            25       2
493         Paint - Red                   4            24       3
492         Paint - Black                 4            14       4
494         Paint - Silver                4            12       5
 (10 row(s) affected)

B.对结果集中的所有行排名

下面的示例返回按薪金排名的前十名员工。 因为未指定 PARTITION BY 子句,所以,RANK 函数应用于结果集中的所有行。

 
 
USE AdventureWorks2012
SELECT TOP(10) BusinessEntityID, Rate, 
RANK() OVER (ORDER BY Rate DESC) AS RankBySalary
FROM HumanResources.EmployeePayHistory AS eph1
WHERE RateChangeDate = (SELECT MAX(RateChangeDate) 
                        FROM HumanResources.EmployeePayHistory AS eph2
                        WHERE eph1.BusinessEntityID = eph2.BusinessEntityID)
ORDER BY BusinessEntityID;

下面是结果集:

 
 
BusinessEntityID Rate                  RankBySalary
---------------- --------------------- --------------------
1                125.50                1
2                63.4615               4
3                43.2692               8
4                29.8462               19
5                32.6923               16
6                32.6923               16
7                50.4808               6
8                40.8654               10
9                40.8654               10
10               42.4808               9
posted @ 2014-09-02 17:51  性能疯子  阅读(17623)  评论(0编辑  收藏  举报
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