Pivot data in T-SQL

Question

I have a group of people. Lets call them A,B,C. I have a table that shows how much they were paid each month....

PERSON|MONTH|PAID
A      JAN   10
A      FEB         


        

Answer 1

If you are using SQL Server 2005 (or above), here is the code:

DECLARE @cols VARCHAR(1000)
DECLARE @sqlquery VARCHAR(2000)

SELECT  @cols = STUFF(( SELECT distinct  ',' + QuoteName([Month])
                        FROM YourTable FOR XML PATH('') ), 1, 1, '') 


SET @sqlquery = 'SELECT * FROM
      (SELECT Person, Month, Paid
       FROM YourTable ) base
       PIVOT (Sum(Paid) FOR [Person]
       IN (' + @cols + ')) AS finalpivot'

EXECUTE ( @sqlquery )

This will work no matter how many different status you have. It dynamically assembles a query with PIVOT. The only way you can do PIVOT with dynamic columns is by assembling the the query dynamically, which can be done in SQL Server.

Other examples:

• SQL Server PIVOT perhaps?
• How do I build a summary by joining to a single table with SQL Server?

Answer 2

I am not sure why you need a dynamic # of columns, since there are always 12 months in a year. Also your month names seem a bit inconsistent in length.

Sample result set:

SELECT * FROM (SELECT 'A' [PERSON],'JAN' [MONTH],'10' [PAID]
UNION SELECT 'A','FEB',20
UNION SELECT 'B','JAN',10
UNION SELECT 'B','FEB',20
UNION SELECT 'B','SEP',30
UNION SELECT 'C','JAN',10
UNION SELECT 'C','JUNE',20
UNION SELECT 'C','JULY',30
UNION SELECT 'C','SEP',40) AS A
PIVOT (SUM([PAID]) FOR [MONTH] IN ([JAN],[FEB],[MARCH],[APRIL],[MAY],[JUNE],[JULY],[AUG],[SEP],[OCT],[NOV],[DEC])) p

Against your table this would become:

SELECT [PERSON],[MONTH],[PAID]
FROM [YOURTABLE]
PIVOT (SUM([PAID]) FOR [MONTH] IN ([JAN],[FEB],[MARCH],[APRIL],[MAY],[JUNE],[JULY],[AUG],[SEP],[OCT],[NOV],[DEC])) p

If you add a year column it looks like this:

SELECT * FROM (SELECT 'A' [PERSON],'JAN' [MONTH],'10' [PAID], 2011 [YEAR]
UNION SELECT 'A','FEB',20, 2011
UNION SELECT 'B','JAN',10, 2011
UNION SELECT 'A','FEB',20, 2010
UNION SELECT 'B','JAN',10, 2010
UNION SELECT 'B','FEB',20,2011
UNION SELECT 'B','SEP',30,2011
UNION SELECT 'C','JAN',10,2011
UNION SELECT 'C','JUNE',20,2011
UNION SELECT 'C','JULY',30,2011
UNION SELECT 'C','SEP',40,2011) AS A
PIVOT (SUM([PAID]) FOR [MONTH] IN ([JAN],[FEB],[MARCH],[APRIL],[MAY],[JUNE],[JULY],[AUG],[SEP],[OCT],[NOV],[DEC])) p