T-SQL 动态枢轴 [英] T-SQL dynamic pivot
本文介绍了T-SQL 动态枢轴的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！
问题描述
好的，我有一张看起来像这样的桌子
Ok I have a table that looks like this
ItemID | ColumnName | Value
1 | name | Peter
1 | phone | 12345678
1 | email | peter@host.com
2 | name | John
2 | phone | 87654321
2 | email | john@host.com
3 | name | Sarah
3 | phone | 55667788
3 | email | sarah@host.com
现在我需要把它变成这个:
Now I need to turn that into this:
ItemID | name | phone | email
1 | Peter | 12345678 | peter@host.com
2 | John | 87654321 | john@host.com
3 | Sarah | 55667788 | sarah@host.com
我一直在研究动态枢轴示例，但似乎我无法将它们放入我的场景中.
I have been looking at dynamic pivot examples, but it seems Im not able to fit them into my scenario.
有人可以帮忙吗?
推荐答案
看下面的例子
CREATE TABLE #Table (
ID INT,
ColumnName VARCHAR(250),
Value VARCHAR(250)
)
INSERT INTO #Table SELECT 1,'name','Peter'
INSERT INTO #Table SELECT 1,'phone','12345678'
INSERT INTO #Table SELECT 1,'email','peter@host.com'
INSERT INTO #Table SELECT 2,'name','John'
INSERT INTO #Table SELECT 2,'phone','87654321'
INSERT INTO #Table SELECT 2,'email','john@host.com'
INSERT INTO #Table SELECT 3,'name','Sarah'
INSERT INTO #Table SELECT 3,'phone','55667788'
INSERT INTO #Table SELECT 3,'email','sarah@host.com'
---I assumed your tablename as TESTTABLE---
DECLARE @cols NVARCHAR(2000)
DECLARE @query NVARCHAR(4000)
SELECT @cols = STUFF(( SELECT DISTINCT TOP 100 PERCENT
'],[' + t.ColumnName
FROM #Table AS t
--ORDER BY '],[' + t.ID
FOR XML PATH('')
), 1, 2, '') + ']'
SELECT @cols
SET @query = N'SELECT ID,'+ @cols +' FROM
(SELECT t1.ID,t1.ColumnName , t1.Value FROM #Table AS t1) p
PIVOT (MAX([Value]) FOR ColumnName IN ( '+ @cols +' ))
AS pvt;'
EXECUTE(@query)
DROP TABLE #Table
这篇关于T-SQL 动态枢轴的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
查看全文
