具有多列的 SQL Pivot

Question

在 sql server 2008 中需要有关 pivot 子句的帮助。 我有一张包含此信息的表格：

Weekno DayOfWeek FromTime ToTime 1 2 10:00 14:00 1 3 10:00 14:00 2 3 08:00 13:00 2 4 09:00 13:00 2 5 14:00 22:00 3 1 06:00 13:00 3 4 06:00 13:00 3 5 14:00 22:00

我想将其转换为如下所示的表格：

周 开始1 结束1 开始2 结束2 开始3 结束3 开始4 结束4 开始5 结束5 开始6 结束6 开始7 结束7 1 10:00 14:00 10:00 14:00 2 08:00 13:00 09:00 13:00 14:00 22:00 3 06:00 13:00 06:00 13:00 14:00 22:00

有什么方法可以处理数据透视查询吗？ 请写一个关于如何做到这一点的例子。

感谢您对此提供的任何帮助。提前致谢。

Answer 1

这是枢轴版本：

https://data.stackexchange.com/stackoverflow/query/7295/so3241450

-- SO3241450

CREATE TABLE #SO3241450 (
    Weekno int NOT NULL
    ,DayOfWeek int NOT NULL
    ,FromTime time NOT NULL
    ,ToTime time NOT NULL
)

INSERT INTO #SO3241450 VALUES
(1, 2, '10:00', '14:00')
,(1, 3, '10:00', '14:00')
,(2, 3, '08:00', '13:00')
,(2, 4, '09:00', '13:00')
,(2, 5, '14:00', '22:00')
,(3, 1, '06:00', '13:00')
,(3, 4, '06:00', '13:00')
,(3, 5, '14:00', '22:00')

;WITH Base AS (
    SELECT Weekno, DayOfWeek, FromTime AS [Start], ToTime AS [End]
    FROM #SO3241450
)
,norm AS (
SELECT Weekno, ColName + CONVERT(varchar, DayOfWeek) AS ColName, ColValue
FROM Base
UNPIVOT (ColValue FOR ColName IN ([Start], [End])) AS pvt
)
SELECT *
FROM norm
PIVOT (MIN(ColValue) FOR ColName IN ([Start1], [End1], [Start2], [End2], [Start3], [End3], [Start4], [End4], [Start5], [End5], [Start6], [End6], [Start7], [End7])) AS pvt​

Answer 2

我认为 CASE WHEN 只有在只有独特的 Weekno 和 DayofWeek 时才有效，因为它只会返回最新开始和结束时间的记录并过滤掉其余的记录。 示例

Weekno    DayOfWeek     FromTime    ToTime
1         2             10:00       14:00
1         2             07:00       09:00
2         3             08:00       13:00
2         4             09:00       13:00

它只会返回 DayofWeek 2 的第 1 周的第一行并跳过第二行。

Answer 3

我个人讨厌枢轴 - 难以阅读且笨拙。

CREATE TABLE #test
(
    WeekNo int,
    [DayOfWeek] int,
    FromTime time,
    ToTime time
    )

INSERT INTO #test
SELECT 1,2,'10:00','14:00'
UNION ALL
SELECT 1,3,'10:00','14:00'
UNION ALL
SELECT 2,3,'08:00','13:00'
UNION ALL
SELECT 2,4,'09:00','13:00'
UNION ALL
SELECT 2,5,'14:00','22:00'
UNION ALL
SELECT 3,1,'06:00','13:00'
UNION ALL
SELECT 3,4,'06:00','13:00'
UNION ALL
SELECT 3,5,'14:00','22:00'

SELECT WeekNo, 
    MAX(CASE WHEN DayOfWeek = 1 THEN FromTime ELSE NULL END)  AS Start1,
    MAX(CASE WHEN DayOfWeek = 1 THEN ToTime ELSE NULL END)  AS End1,
    MAX(CASE WHEN DayOfWeek = 2 THEN FromTime ELSE NULL END)  AS Start2,
    MAX(CASE WHEN DayOfWeek = 2 THEN ToTime ELSE NULL END)  AS End2,
    MAX(CASE WHEN DayOfWeek = 3 THEN FromTime ELSE NULL END)  AS Start3,
    MAX(CASE WHEN DayOfWeek = 3 THEN ToTime ELSE NULL END)  AS End3,
    MAX(CASE WHEN DayOfWeek = 4 THEN FromTime ELSE NULL END)  AS Start4,
    MAX(CASE WHEN DayOfWeek = 4 THEN ToTime ELSE NULL END)  AS End4,
    MAX(CASE WHEN DayOfWeek = 5 THEN FromTime ELSE NULL END)  AS Start5,
    MAX(CASE WHEN DayOfWeek = 5 THEN ToTime ELSE NULL END)  AS End5,
    MAX(CASE WHEN DayOfWeek = 6 THEN FromTime ELSE NULL END)  AS Start6,
    MAX(CASE WHEN DayOfWeek = 6 THEN ToTime ELSE NULL END)  AS End6,
    MAX(CASE WHEN DayOfWeek = 7 THEN FromTime ELSE NULL END)  AS Start7,
    MAX(CASE WHEN DayOfWeek = 7 THEN ToTime ELSE NULL END)  AS End7
    FROM #test
    GROUP BY WeekNo

它会把袜子从枢轴上吹下来；性能方面。