有毛病我旋轉功能，但我真的不知道爲什麼

Question

我有了Order_Day，PRODUCT_ID，數量和價格列的表：

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 

的問題是，我想選擇order_day，PRODUCT_ID，和TotalSales（這可以通過使用數量乘以價格來計算），然後對其進行調整。因此，旋轉表應該有三列：product_id，'01 -JUL-11'，'02-JUL-11'。所以我用的代碼如下：

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 

但它返回如下結果：

Answer 1

'2011-07-01'是一個常量字符串。在SQL Server中的逃生方法使用方括號：

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

Answer 2

你想是這樣的

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; 

輸出將是：

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

Answer 3

這個查詢會做的伎倆 -

;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 

它會給你以下輸出 -

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

Answer 4

我在過去幾個月中看到過數百個關鍵問題。讓我發表一些樣本解決方案，也許可以幫助其他人學習基礎知識，所以我們不會一遍又一遍地看到相同的東西。

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; 

結果：

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 

你甚至可以做一個動態的支點，當你不知道，時間提前，所有字段，你將被處理。讓SQL Server爲您做好工作！

--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 

你會在這裏找到一些很好的資源！

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/