Question

是否可以在SQL中按列排序而不是按行排序？我不需要基本的ORDER BY语句，我知道这些是如何工作的（即：按column1，column2等命令）。

基本上尝试对这样的事情进行排序：

column 1    column 2    column 3
   1            0           3

试图对此进行排序：

column 3    column 1    column 2
   3           1           0

这在SQL中是否可行？最好是t-sql或将在sql server 2005上运行的任何东西

我一直在网上搜索这几个小时，似乎没有人想问这个问题。或者我吮吸搜索。

   ; with numbered as
   (
     select SUM(OrderReceived) as c1, SUM(OrderOnHold) as c2, SUM(OrderConfirmed) as     c3,
     row_number() over (order by employee) RecordNumber
     from( SELECT 


e.FirstName+' '+e.LastName AS Employee
,CASE WHEN oim.MilestoneID = 10 THEN 1 ELSE 0 END as OrderReceived
,CASE WHEN oim.MilestoneID = 15 THEN 1 ELSE 0 END as OrderOnHold
,CASE WHEN oim.MilestoneID = 20 THEN 1 ELSE 0 END as OrderConfirmed
FROM OrderItems oi
    JOIN Orders o on o.orderid = oi.orderid
    JOIN OrderItemMilestones oim on oim.orderid = oi.orderid and oim.orderitemid     =     oi.orderitemid
    JOIN Milestones m on m.milestoneid = oim.milestoneid
    JOIN Employees e on e.username = oim.recordedbyuser
    JOIN Clients cl on cl.clientid = o.clientid
WHERE oim.MilestoneDate Between '2012-08-01' and '2012-08-05'
    and e.terminationdate is null
),

ordered as
(
 select SUM(OrderReceived) as c1, SUM(OrderOnHold) as c2, SUM(OrderConfirmed) as c3,
         row_number() over (partition by RecordNumber
                           order by employee desc) rn
    from numbered

  unpivot (v for c in (c1, c2, c3)) u
)
select RecordNumber,
     [1] c1,
     [2] c2,
     [3] c3
 from 
 (
 select RecordNumber,
         v,
         Rn
    from ordered
  ) o
 pivot (min(employee) for Rn in ([1], [2], [3])) p

Answer 1

这是对列进行排序的相对简单的方法。如果您首先unpivot，排序并pivot您的数据，您将获得排序列。

Here is Sql Fiddle with example

-- Assign arbitrary numbers to records
-- You might skip this part if you have unique column
-- in which case you should replace RecordNumber with this ID
; with numbered as
(
  select *,
         row_number() over (order by (select null)) RecordNumber
    from test
),
-- Generate order by
-- For all the columns in record.
-- Rn will always be in range
-- 1..NumberOfColumns
-- Order is done on unpivoted data
ordered as
(
  select *,
         row_number() over (partition by RecordNumber
                            order by v desc) rn
    from numbered
 -- list all the columns here
 -- v is for value
 -- c is for column
 unpivot (v for c in (c1, c2, c3)) u
)
-- Finally return the data in original layout
select RecordNumber,
       [1] c1,
       [2] c2,
       [3] c3
  from 
  (
    -- Only the columns needed by the query
    -- Pivot will not play nice even if you
    -- Select only subset of columns in
    -- outer query
    select RecordNumber,
           v,
           Rn
      from ordered
  ) o
 -- Get value for row numbers 1..NumberOfColumns
 pivot (min(v) for Rn in ([1], [2], [3])) p

您可能希望添加标题行，以便了解哪个值来自哪个列。要做到这一点，我会添加一个标识标题/行的列，将所有标题联合到o以获取相应的标题和顺序，以确保这两行保持在一起：

  (
    select RecordNumber,
           v,
           Rn,
           1 HdrRow
      from ordered
     union all
    select RecordNumber,
           c,    -- Column name is in c
           Rn,
           0 HdrRow
      from ordered
  ) o
    ...
  order by RecordNumber, HdrRow

Answer 2

您使用的是SELECT *吗？如果是这样，请停止这样做。如果你知道你希望它们以这种方式列出，那么写下：

SELECT [column 3], [column 1], [column 2] FROM dbo.table;

如果你的意思是想要在这些列中进行排序，我不确定它会有多么有意义。但我猜你可以这样做：

DECLARE @x TABLE(c1 INT, c2 INT, c3 INT);

INSERT @x(c1,c2,c3) SELECT 2,1,3
UNION ALL SELECT 3,4,5
UNION ALL SELECT 5,4,3
UNION ALL SELECT 3,1,2
UNION ALL SELECT 3,3,3
UNION ALL SELECT 3,4,3
UNION ALL SELECT 4,3,4;

SELECT c1 = CASE
  WHEN c1 >= c2 AND c1 >= c3 THEN c1
  WHEN c2 >= c1 AND c2 >= c3 THEN c2
  ELSE c3 END,
c2 = CASE 
  WHEN c1 >= c2 AND c1 >= c3 THEN 
    CASE WHEN c2 >= c3 THEN c2 ELSE c3 END
  WHEN c2 >= c1 AND c2 >= c3 THEN
    CASE WHEN c1 >= c3 THEN c1 ELSE c3 END
  ELSE
    CASE WHEN c1 >= c2 THEN c1 ELSE c2 END
  END,
c3 = CASE
  WHEN c1 <= c2 AND c1 <= c3 THEN c1
  WHEN c2 <= c1 AND c2 <= c3 THEN c2
  ELSE c3 END
FROM @x;

结果：

c1   c2   c3
---- ---- ----
3    2    1
5    4    3
5    4    3
3    2    1
3    3    3
4    3    3
4    4    3

Answer 3

使用动态查询的双重查询

如果您的查询只返回一行，那么您可以通过执行两次查询来解决此问题：

查询您的数据以获取列的值 a）和根据结果
执行动态查询

如果您的查询应该返回多行数据，我想我们需要更多信息，您需要提供一些可行的解决方案，或者至少是一个更好的建议如何缓解您的问题。< / p>

按列排序结果而不是行

3 个答案:

使用动态查询的双重查询