Q:

Row over partition for totaling data by month

I have some data that I need to sum for each month and I am having trouble figuring out how to get it to have 12 columns (one for each month) with the sum total for that month.
Example: 
Data as is:
GrossAmt    ClaimDate
49764.00    2014-08-21 00:00:00.000
1382.43     2014-08-27 00:00:00.000
602.77      2014-09-02 00:00:00.000
497.04      2014-09-02 00:00:00.000

desired result:
GrossAmt    ClaimDate
51146.43    August
1099.81     September

actual Desired Result:
July  August    September
0     51146.43  1099.81

Sorry I did not include this before!
I am sure that this is the most basic example of using row over partition perhaps it is my lack of programming background but this is one concepts that I just can not wrap my head around.  
This is what I have so far but I am not sure where to go next. 
With CTE ([GrossAmt],ClaimMonth)
AS(
SELECT TOP 10000 
       Sum([GrossAmt]) as TotalClaimAmt
      ,CASE WHEN Month([ClaimDate]) = 1 THEN 'January'
            WHEN Month([ClaimDate]) = 2 THEN 'February'
            WHEN Month([ClaimDate]) = 3 THEN 'March'
            WHEN Month([ClaimDate]) = 4 THEN 'April'
            WHEN Month([ClaimDate]) = 5 THEN 'May'
            WHEN Month([ClaimDate]) = 6 THEN 'June'
            WHEN Month([ClaimDate]) = 7 THEN 'July'
            WHEN Month([ClaimDate]) = 8 THEN 'August'
            WHEN Month([ClaimDate]) = 9 THEN 'September'
            WHEN Month([ClaimDate]) = 10 THEN 'October'
            WHEN Month([ClaimDate]) = 11 THEN 'November'
            WHEN Month([ClaimDate]) = 12 THEN 'Decmber'
        End  AS ClaimMonth
  FROM [Database].[dbo].[Table]
    )
    Group BY  [ClaimDate]
    )
  Select * From CTE

Perhaps what I might need is a basic lesson on how Row over partition works.  I have tried reading articles I have found online but none seem to make sense to me, They are way to advanced and I get lost right away, Also it does not help that I do not learn very well by reading, I need to see it in action, and understand how it works. 
Anyway, thanks for the help.  You guys rock!
EDIT: 
actual Desired Result:
July  August    September
0     51146.43  1099.81

Sorry I did not include this before!    

A:

You need to use PIVOT to get the desired results
CTE is doing the Monthly aggregation and PIVOT is used to convert the CTE result rows into horizontal columns
;With CTE ([GrossAmt],MonthVal)
AS(
SELECT TOP 10000 
       Sum([GrossAmt]) as GrossAmt,
       DATEADD(MONTH, DATEDIFF(MONTH,0,ClaimDate), 0) as MonthVal
  FROM [Table1]
  Group BY  DATEADD(MONTH, DATEDIFF(MONTH,0,ClaimDate), 0)
)
SELECT * FROM
(Select [GrossAmt], DATENAME(MONTH,MonthVal) as ClaimMonth From CTE) t
PIVOT
( MAX(GrossAmt) for ClaimMonth  in 
  ( [January], [Febrauary], [March], [April], [May], [June], [July],  
    [August],  [September], [October], [November], [December] 

  )
)pvt

