Pivot dynamic column - sql

Question

I have a table with the following values.
Date TCOUNT COUNT
02/06/2013 00:00 3500 35
02/12/2013 00:00 4000 23
02/21/2013 00:00 1000 54
02/27/2013 00:00 5000 12
where Date is dynamic col need to be pivoted.
I need to pivote the above table to get the below result
02/06/2013 00:00 02/12/2013 00:00 02/21/2013 00:00 02/27/2013 00:00
35 23 54 12
3500 4000 1000 5000
please help.
Thanks.

Answer 1

Based on the fact that your previous question was tagged with sql server, I am guessing that you need sql server syntax.
In order to get the result, you will need to use both the UNPIVOT and the PIVOT functions. The unpivot will take the TCount and Count columns and convert them to rows and then the PIVOT will take the dates and convert them to columns.
If you know the values ahead of time then you can hard-code the query:
select *
from
(
select date, value, col
from yourtable
unpivot
(
value
for col in (tcount, count)
) unpiv
) src
pivot
(
max(value)
for date in ([2013-02-06], [2013-02-12],
[2013-02-21], [2013-02-27])
) piv;
See SQL Fiddle with Demo
However, if you have an unknown number of dates, then you will need dynamic SQL:
DECLARE #cols AS NVARCHAR(MAX),
#query AS NVARCHAR(MAX)
select #cols = STUFF((SELECT distinct ',' + QUOTENAME(convert(varchar(10), Date, 120))
from yourtable
FOR XML PATH(''), TYPE
).value('.', 'NVARCHAR(MAX)')
,1,1,'')
set #query = 'SELECT col, ' + #cols + ' from
(
select convert(varchar(10), Date, 120) date,
value, col
from yourtable
unpivot
(
value
for col in (tcount, count)
) unpiv
) src
pivot
(
max(value)
for date in (' + #cols + ')
) p '
execute(#query)
See SQL Fiddle with Demo
The result of both is:
| COL | 2013-02-06 | 2013-02-12 | 2013-02-21 | 2013-02-27 |
--------------------------------------------------------------
| COUNT | 35 | 23 | 54 | 12 |
| TCOUNT | 3500 | 4000 | 1000 | 5000 |