6

我有一张相当宽的桌子，我想把它改成高的。目前的数据是这样的：

VEND   YEAR   I1_DOLS   I1_QTY   I2_DOLS   I2_QTY   I3_DOLS   I3_QTY ...
1234   2011   101587    508      203345    334      105938    257
1234   2012   257843    587      235883    247      178475    456
1011   2010   584737    432      587274    356      175737    563
1011   2011   517774    356      483858    456      481785    354

我想将其转换为如下所示的表：

VEND   YEAR   MONTH   DOLS     QTY
1234   2011   1       101587   508
1234   2011   2       203345   334
1234   2011   3       105938   257
1234   2012   1       257843   587
1234   2012   2       235883   247
.
.
.

我认为 PIVOT 是我需要的，但我似乎无法弄清楚这一点。

4

1 回答 1

9

您可以使用CROSS APPLY (VALUES). 这是一篇文章来解释这是如何完成的：

http://www.sqlservercentral.com/articles/CROSS+APPLY+VALUES+UNPIVOT/91234/

基本上代码是：

SELECT vend,
  year,
  month,
  dols, 
  qty
FROM YourTable t
CROSS APPLY 
(
    VALUES
        (1, I1_DOLS, I1_QTY),
        (2, I2_DOLS, I2_QTY),
        (3, I3_DOLS, I3_QTY)
) x (month, dols, qty);

请参阅带有演示的 SQL Fiddle

或者您可以使用UNION ALL查询：

select vend, year, 1 month, [I1_DOLS] Dols, [I1_QTY] Qty
from yourtable
union all
select vend, year, 2 month, [I2_DOLS] Dols, [I2_QTY] Qty
from yourtable
union all
select vend, year, 3 month, [I3_DOLS] Dols, [I3_QTY] Qty
from yourtable

请参阅带有演示的 SQL Fiddle

或者您甚至可以同时应用UNPIVOT和PIVOT函数来转换数据：

select *
from
(
  select vend,
    year,
    replace(replace(replace(col, 'I', ''), '_Dols', ''), '_Qty', '') month,
    case when col like '%Dols%' then 'dols' else 'qty' end col_name,
    value
  from 
  (
    select vend, year, [I1_DOLS], [I1_QTY], [I2_DOLS], [I2_QTY], [I3_DOLS], [I3_QTY]
    from yourtable
  ) src
  unpivot
  (
    value
    for col in ([I1_DOLS], [I1_QTY], [I2_DOLS], [I2_QTY], [I3_DOLS], [I3_QTY])
  ) un
) unp
pivot
(
  max(value)
  for col_name in (dols, qty)
) piv

请参阅SQL Fiddle with Demo。

这三个都会给出相同的结果：

| VEND | YEAR | MONTH |   DOLS | QTY |
--------------------------------------
| 1234 | 2011 |     1 | 101587 | 508 |
| 1234 | 2011 |     2 | 203345 | 334 |
| 1234 | 2011 |     3 | 105938 | 257 |
| 1234 | 2012 |     1 | 257843 | 587 |
| 1234 | 2012 |     2 | 235883 | 247 |
| 1234 | 2012 |     3 | 178475 | 456 |
| 1011 | 2010 |     1 | 584737 | 432 |
| 1011 | 2010 |     2 | 587274 | 356 |
| 1011 | 2010 |     3 | 175737 | 563 |
| 1011 | 2011 |     1 | 517774 | 356 |
| 1011 | 2011 |     2 | 483858 | 456 |
| 1011 | 2011 |     3 | 481785 | 354 |
于 2013-01-25T22:52:57.413 回答