有毛病我旋转功能，但我真的不知道为什么

Question

我有了Order_Day，PRODUCT_ID，数量和价格列的表：

create table dbo.AmazonTestTable 
(order_day date, 
order_id int, 
product_id char(2), 
quantity int, 
price int) 
go 

insert into dbo.AmazonTestTable values 
('01-JUL-11',1,'p1',5,5), 
('01-JUL-11',2,'p2',2,10), 
('01-JUL-11',3,'p3',10,25), 
('01-JUL-11',4,'p1',20,5), 
('02-JUL-11',5,'p3',5,25), 
('02-JUL-11',6,'p4',6,20), 
('02-JUL-11',7,'p1',2,5), 
('02-JUL-11',8,'p5',1,50), 
('02-JUL-11',9,'p6',2,50), 
('02-JUL-11',10,'p2',4,10) 
go 

的问题是，我想选择order_day，PRODUCT_ID，和TotalSales（这可以通过使用数量乘以价格来计算），然后对其进行调整。因此，旋转表应该有三列：product_id，'01 -JUL-11'，'02-JUL-11'。所以我用的代码如下：

select product_id,'2011-07-01' as TotalSalesOnDay1,'2011-07-02' as 
TotalSalesOnDay2 
from (select product_id,order_day,(quantity*price) as TotalSales 
     from dbo.AmazonTestTable) as TotalSalesPerDay 
pivot 
(sum(TotalSales) for [order_day] in ([2011-07-01] ,[2011-07-02])) as 
PivotDataSet; 
go 

但它返回如下结果：

Answer 1

'2011-07-01'是一个常量字符串。在SQL Server中的逃生方法使用方括号：

select product_id, [2011-07-01] as TotalSalesOnDay1, [2011-07-02] as TotalSalesOnDay2 
. . . 

Answer 2

你想是这样的

SELECT product_id, order_day, SUM(TotalSales) AS TotalSales FROM 
     (SELECT product_id,order_day,(quantity*price) as TotalSales 
     FROM AmazonTestTable) AS TotalSalesPerDay 
    GROUP BY TotalSalesPerDay.order_day; 

输出将是：

product_id| order_day | TotalSales 
p1  | 01-JUL-11 |395 
p2  | 02-JUL-11 |445 

Answer 3

这个查询会做的伎俩 -

;With PivotData 
As 
(
    Select 
     product_id, -- grouping element 
     order_day, -- spreading element 
     (quantity * price) As TotalSales -- aggregating element 
    From AmazonTestTable 
) 
Select 
    product_id, [2011-07-01] As TotalSalesDay1, [2011-07-02] As TotalSalesDay2 
From PivotData 
Pivot (Sum(TotalSales) For order_day In ([2011-07-01], [2011-07-02])) As P 

它会给你以下输出 -

product_id TotalSalesDay1 TotalSalesDay2 
p1   125    10 
p2   20    40 
p4   NULL   120 
p3   250    125 
p5   NULL   50 
p6   NULL   100 

Answer 4

我在过去几个月中看到过数百个关键问题。让我发表一些样本解决方案，也许可以帮助其他人学习基础知识，所以我们不会一遍又一遍地看到相同的东西。

CREATE TABLE Products (
product VARCHAR(30), 
market_year INT, 
value INT, 
quantity INT, 
CONSTRAINT pk_products 
PRIMARY KEY (product, market_year)); 

INSERT INTO Products VALUES('Corn', 2003, 100, 20); 
INSERT INTO Products VALUES('Corn', 2004, 200, 25); 
INSERT INTO Products VALUES('Corn', 2005, 150, 30); 
INSERT INTO Products VALUES('Corn', 2006, 150, 10); 

SELECT product, 
     SUM(CASE WHEN market_year = 2003 THEN value ELSE 0 END) AS v2003, 
     SUM(CASE WHEN market_year = 2003 THEN quantity ELSE 0 END) AS q2003, 
     SUM(CASE WHEN market_year = 2004 THEN value ELSE 0 END) AS v2004, 
     SUM(CASE WHEN market_year = 2004 THEN quantity ELSE 0 END) AS q2004, 
     SUM(CASE WHEN market_year = 2005 THEN value ELSE 0 END) AS v2005, 
     SUM(CASE WHEN market_year = 2005 THEN quantity ELSE 0 END) AS q2005, 
     SUM(CASE WHEN market_year = 2006 THEN value ELSE 0 END) AS v2006, 
     SUM(CASE WHEN market_year = 2006 THEN quantity ELSE 0 END) AS q2006 
FROM Products 
GROUP BY product; 

结果：

product v2003 q2003 v2004 q2004 v2005 q2005 v2006 q2006 
Corn 100 20 200 25 150 30 150 10 

也。 。 。

USE AdventureWorks 
GO 
-- Creating Test Table 
CREATE TABLE Product(Cust VARCHAR(25), Product VARCHAR(20), QTY INT) 
GO 
-- Inserting Data into Table 
INSERT INTO Product(Cust, Product, QTY) 
VALUES('KATE','VEG',2) 
INSERT INTO Product(Cust, Product, QTY) 
VALUES('KATE','SODA',6) 
INSERT INTO Product(Cust, Product, QTY) 
VALUES('KATE','MILK',1) 
INSERT INTO Product(Cust, Product, QTY) 
VALUES('KATE','BEER',12) 
INSERT INTO Product(Cust, Product, QTY) 
VALUES('FRED','MILK',3) 
INSERT INTO Product(Cust, Product, QTY) 
VALUES('FRED','BEER',24) 
INSERT INTO Product(Cust, Product, QTY) 
VALUES('KATE','VEG',3) 
GO 
-- Selecting and checking entires in table 
SELECT * 
FROM Product 
GO 
-- Pivot Table ordered by PRODUCT 
SELECT PRODUCT, FRED, KATE 
FROM (
SELECT CUST, PRODUCT, QTY 
FROM Product) up 
PIVOT (SUM(QTY) FOR CUST IN (FRED, KATE)) AS pvt 
ORDER BY PRODUCT 
GO 
-- Pivot Table ordered by CUST 
SELECT CUST, VEG, SODA, MILK, BEER, CHIPS 
FROM (
SELECT CUST, PRODUCT, QTY 
FROM Product) up 
PIVOT (SUM(QTY) FOR PRODUCT IN (VEG, SODA, MILK, BEER, CHIPS)) AS pvt 
ORDER BY CUST 
GO 
-- Unpivot Table ordered by CUST 
SELECT CUST, PRODUCT, QTY 
FROM 
(
SELECT CUST, VEG, SODA, MILK, BEER, CHIPS 
FROM (
SELECT CUST, PRODUCT, QTY 
FROM Product) up 
PIVOT 
(SUM(QTY) FOR PRODUCT IN (VEG, SODA, MILK, BEER, CHIPS)) AS pvt) p 
UNPIVOT 
(QTY FOR PRODUCT IN (VEG, SODA, MILK, BEER, CHIPS) 
) AS Unpvt 
GO 
-- Clean up database 
DROP TABLE Product 
GO 

ResultSet: 
-- Selecting and checking entires in table 
Cust Product QTY 
------------------------- -------------------- ----------- 
KATE VEG 2 
KATE SODA 6 
KATE MILK 1 
KATE BEER 12 
FRED MILK 3 
FRED BEER 24 
KATE VEG 3 

-- Pivot Table ordered by PRODUCT 
PRODUCT FRED KATE 
-------------------- ----------- ----------- 
BEER 24 12 
MILK 3 1 
SODA NULL 6 
VEG NULL 5 

-- Pivot Table ordered by CUST 
CUST VEG SODA MILK BEER CHIPS 
------------------------- ----------- ----------- ----------- ----------- ----------- 
FRED NULL NULL 3 24 NULL 
KATE 5 6 1 12 NULL 

-- Unpivot Table ordered by CUST 
CUST PRODUCT QTY 
------------------------- -------- ----------- 
FRED MILK 3 
FRED BEER 24 
KATE VEG 5 
KATE SODA 6 
KATE MILK 1 
KATE BEER 12 12 

你甚至可以做一个动态的支点，当你不知道，时间提前，所有字段，你将被处理。让SQL Server为您做好工作！

--Create Temporary Table #CourseSales 
CREATE TABLE #CourseSales 
(Course VARCHAR(50),Year INT,Earning MONEY) 
GO 
--Populate Sample records 
INSERT INTO #CourseSales VALUES('.NET',2012,10000) 
INSERT INTO #CourseSales VALUES('Java',2012,20000) 
INSERT INTO #CourseSales VALUES('.NET',2012,5000) 
INSERT INTO #CourseSales VALUES('.NET',2013,48000) 
INSERT INTO #CourseSales VALUES('Java',2013,30000) 
GO 

SELECT * 
FROM #CourseSales 
PIVOT(SUM(Earning) 
     FOR Course IN ([.NET], Java)) AS PVTTable 

你会在这里找到一些很好的资源！

http://blogs.lessthandot.com/index.php/DataMgmt/DataDesign/understanding-sql-server-2000-pivot/

http://blogs.lessthandot.com/index.php/DataMgmt/DataDesign/dynamic-pivot-on-multiple-columns/