我的情况是这样的:
我有400个用户(行)的调查,回答了76个问题(列)。这些用户已在数据库中拥有ID。我创建了一个包含每个公司问题的表,每个问题都有自己的ID。所以现在我需要将问题ID与每个用户ID的答案结合起来。
导入时,列标题必须为:
User ID | Question ID | Answer
xxxxxxx | xxxxxxxxxxxxx | xxxxxxxxxx
而不是:
User ID | Question ID 1 | Question ID 2 | Question ID 3 | etc...
xxxxxx | xxxxx | xxxxx | xxxxx | ...
感谢所有的帮助,谢谢。
答案 0 :(得分:2)
听起来你想要UNPIVOT数据。根据您的SQL Server版本,有几种方法可以完成此操作。
如果您使用的是SQL Server 2005+,则可以使用UNPIVOT函数将列转换为行:
select userid, questionid, answer
from yourtable
unpivot
(
answer
for questionId in (QuestionId1, QuestionId2)
) unpiv;
如果您使用的是SQL Server 2008+,则可以使用UNPIVOT函数,但也可以使用CROSS APPLY和VALUES将数据从列转换为行:
select t.userid, c.questionid, c.answer
from yourtable t
cross apply
(
values
('QuestionId1', QuestionId1),
('QuestionId2', QuestionId2),
...
) c (questionId, answer);
然后,如果您需要将未知数量的列转换为行,则可以使用动态SQL来获取结果:
DECLARE @colsUnpivot AS NVARCHAR(MAX),
@query AS NVARCHAR(MAX)
select @colsUnpivot = stuff((select ','+quotename(C.name)
from sys.columns as C
where C.object_id = object_id('yourtable') and
C.name != 'userid'
for xml path('')), 1, 1, '')
set @query
= 'select userid, questionid, answer
from yourtable
unpivot
(
answer
for questionid in ('+ @colsunpivot +')
) u'
exec(@query);
作为旁注,当您执行此类转换时,要转换为行的列的数据必须是相同的数据类型。例如,如果Question1和Question2是不同的数据类型,那么你需要在unpivot之前转换它们,类似于:
select userid, questionid, answer
from
(
select userid,
cast(questionid1 as varchar(10)) questionid1,
cast(questionid2 as varchar(10)) questionid2
from yourtable
) src
unpivot
(
answer
for questionId in (QuestionId1, QuestionId2)
) unpiv;
答案 1 :(得分:1)
您可以在MSSQL 2005或更高版本中使用unpivot:
SELECT [User ID], [Question ID], [Question Reponse]
FROM
(SELECT [User ID], [Question 1], [Question 2]
FROM pvt) p
UNPIVOT
([Question Reponse] FOR [Question ID] IN
([Question 1], [Question 2])
)AS unpvt;
自: [用户ID] int ,[问题1] VARCHAR(100) ,[问题2] VARCHAR(100)
结果:
| USER ID | QUESTION ID | QUESTION REPONSE |
--------------------------------------------
| 1 | Question 1 | Blah |
| 1 | Question 2 | BlahBlah |
| 2 | Question 1 | MoreBlah |
| 3 | Question 1 | No Response |
| 3 | Question 2 | Else |