透视依据出现次数在SQL Server 2008

Question

我有数据，如下列：

我想透视数据，看起来像这样。每个尺寸最多有三个oPack值，并且我希望每个“类别+类别2 +尺寸”组合的所有oPack值在最后3列中按升序排列。

Category | Category2 | Size  | Pack1 | Pack2 | Pack3 
Chilled... Chilled  1.75-1.89L 1750 1890 NULL 
Chilled... Chilled  1.75/1.89L 1750 1890 NULL 
Chilled... Chilled  1.75L  1750 NULL NULL 
Chilled... Chilled  1.89/2.63L 1890 2630 NULL 
... 
Chilled... Chilled  400-710mL 400  NULL NULL 

我想是这样的：

select [Category],[Category2], [Pack1], [Pack2], [Pack3] 
from (
    select [Category],[Category2],[size], oPack 
    from myTable) p 
pivot (Max(oPack) for oPack in ([Pack1], [Pack2], [Pack3])) as pvt 

Answer 1

这使正是你要寻找的。首先，一个小桌子的准备。

IF object_id('tempdb.dbo.#Drinks') IS NOT NULL DROP TABLE #Drinks; 
GO 
CREATE TABLE #Drinks (
    Category1 varchar(40), 
    Category2 varchar(40), 
    Size varchar(20), 
    Pack int 
); 

INSERT #Drinks VALUES 
    ('Chilled Juices & Drinks', 'Chilled', '1.75-1.89L', 1750), 
    ('Chilled Juices & Drinks', 'Chilled', '1.75-1.89L', 1890), 
    ('Chilled Juices & Drinks', 'Chilled', '1.75/1.89L', 1750), 
    ('Chilled Juices & Drinks', 'Chilled', '1.75/1.89L', 1890), 
    ('Chilled Juices & Drinks', 'Chilled', '1.75', 1750), 
    ('Chilled Juices & Drinks', 'Chilled', '1.89/2.63L', 1890), 
    ('Chilled Juices & Drinks', 'Chilled', '1.89/2.63L', 2630), 
    ('Chilled Juices & Drinks', 'Chilled', '1.89L', 1890), 
    ('Chilled Juices & Drinks', 'Chilled', '1L', 1000), 
    ('Chilled Juices & Drinks', 'Chilled', '1L', 1000), 
    ('Chilled Juices & Drinks', 'Chilled', '2.63L', 2630), 
    ('Chilled Juices & Drinks', 'Chilled', '2.84L', 2840), 
    ('Chilled Juices & Drinks', 'Chilled', '250mL', 250), 
    ('Chilled Juices & Drinks', 'Chilled', '3.78L', 3780), 
    ('Chilled Juices & Drinks', 'Chilled', '355mL', 355), 
    ('Chilled Juices & Drinks', 'Chilled', '400-710mL', 400), 
    ('Frozen Juices', 'Frozen', '1.60L', 1600), 
    ('Frozen Juices', 'Frozen', '1.40L', 1400); 

然后，你的解决方案：

WITH Nums AS (
    SELECT 
     *, 
     'Pack' + Convert(varchar(30), Dense_Rank() OVER (
     PARTITION BY Category1, Category2, Size ORDER BY Pack) 
     ) PackNum 
    FROM #Drinks 
) 
SELECT 
    * 
FROM 
    Nums 
    PIVOT (Max(Pack) FOR PackNum IN (Pack1, Pack2, Pack3)) P; 

而且，一个替代的解决方案可能是有用的：

SELECT 
    * 
FROM 
    #Drinks 
    PIVOT (Max(Pack) FOR Pack IN (
     [250], [355], [400], [1000], [1400], [1600], 
     [1750], [1890], [2630], [2840], [3780] 
    )) P;