Question

输入表

country tag short
UK  F1  Units
UK  F2  Volume
UK  F3  Value
FR  T3  Units
FR  T2  Volume
FR  T1  Value

我想要的结果输出：

country Units Volume Value
uk      f1      f2      f3
fr      t1      t2      t3

Answer 1

如果有固定数量的不同short值，只需使用case表达式进行条件聚合

select country,
       max(case when short = 'Units' then tag end) as Units,
       max(case when short = 'Volume' then tag end) as Volume,
       max(case when short = 'Value' then tag end) as val
from tablename
group by country

Answer 2

对于解决方案，您必须使用动态数据透视。

//to expand the buttons:
topFab.animate().rotationBy(180);
fab2.animate().translationY(-150);
fab3.animate().translationY(-300);
fab4.animate().translationY(-450);

//to collapse them:
topFab.animate().rotationBy(-180);
fab2.animate().translationY(0);
fab3.animate().translationY(0);
fab4.animate().translationY(0);

Answer 3

表结构

 CREATE TABLE tablename
  (
     [country] [NVARCHAR](10) NULL,
     [tag]     [NVARCHAR](10) NULL,
     [short]   [NVARCHAR](10) NULL
  )

INSERT INTO tablename
VALUES      
('UK','F1','Units'),
('UK','F2','Volume'),
('UK','F3','Value'),
('FR','T3','Units'),
('FR','T2','Volume'),
('FR','T1','Value');

使用数据透视功能

SELECT *
FROM   tablename
       PIVOT ( Max(tag)
             FOR short IN ([Units], [volume], [Value]) ) piv;

^{在线演示：Link}

使用动态SQL PIVOT

DECLARE @cols  AS NVARCHAR(max),
        @query AS NVARCHAR(max)

SELECT @cols = Stuff((SELECT distinct ',' + Quotename(short)
                      FROM   tablename
                      FOR xml path(''), type).value('.', 'NVARCHAR(MAX)'), 1, 1,'');

SET @query = 'SELECT * 
              FROM   tablename        
                     PIVOT ( Max(tag)              
                           FOR short IN (' + @cols + ') ) piv;';

EXECUTE(@query);

^{在线演示：Link}

结果

+---------+-------+--------+-------+
| country | Units | volume | Value |
+---------+-------+--------+-------+
| FR      | T3    | T2     | T1    |
| UK      | F1    | F2     | F3    |
+---------+-------+--------+-------+

从一张表透视数据

3 个答案: