我在SQL server 2008中有下表。请帮助获得预期的输出
感谢。
CREATE TABLE [dbo].[Test]([Category] [varchar](10) NULL,[Value] [int] NULL,
[Weightage] [int] NULL,[Rn] [smallint] NULL ) ON [PRIMARY]
insert into Test values ('Cat1',310,674,1),('Cat1',783,318,2),('Cat1',310,96,3),('Cat1',109,917,4),('Cat2',441,397,1),('Cat2',637,725,2),('Cat2',460,742,3),('Cat2',542,583,4),('Cat2',601,162,5),('Cat2',45,719,6),('Cat2',46,305,7),('Cat3',477,286,1),('Cat3',702,484,2),('Cat3',797,836,3),('Cat3',541,890,4),('Cat3',750,962,5),('Cat3',254,407,6),('Cat3',136,585,7),('Cat3',198,477,8),('Cat4',375,198,1),('Cat4',528,351,2),('Cat4',845,380,3),('Cat4',716,131,4),('Cat4',781,919,5)
答案 0 :(得分:1)
按类别平均重量
SELECT
Category,
AVG(Value),
SUM(CASE WHEN RN<4 THEN Weightage ELSE 0 END) / (NULLIF(SUM(CASE WHEN RN<4 THEN 1 ELSE 0 END), 0))
FROM
MyTable
GROUP BY
Category
整套的平均重量
SELECT
M.Category,
AVG(Value),
foo.AvgWeightage
FROM
MyTable M
CROSS JOIN
(SELECT AVG(Weightage) As AvgWeightage FROM MyTable WHERE Rn < 4) foo
GROUP BY
M.Category, foo.AvgWeightage
答案 1 :(得分:1)
简单:)
SELECT Category,
AVG(Value) AS AvgValue,
AVG(CASE WHEN RN< 4 THEN (Weightage) END ) AS AvgWeightage
FROM Test
GROUP BY Category
答案 2 :(得分:0)
试试这个
SELECT AvgValue.Category, AvgValue.AvgValue, AvgWeight.Weight
FROM(
(SELECT c.Category,
AVG(c.Value) AS AvgValue
FROM Test c
GROUP BY Category) AvgValue
INNER JOIN
(SELECT Category, AVG(Weightage) AS Weight
FROM Test
WHERE Rn < 4
GROUP BY Category) AvgWeight
ON AvgValue.Category = AvgWeight.Category)