历史滚动每日总和

Question

I have a table of consisting of Dates and the amount of revenue recorded for that day going back for about 12 years. What I would like to do with this data is create a new table with Dates and prior 7-day revenue numbers. Any guidance would be greatly appreciated. Below is an example of what my source table and what my results would need to look like....

Source Table..

DATE       |   Revenue
12/31/2013 |   200
12/30/2013 |   300
12/29/2013 |   400
12/28/2013 |   100
12/27/2013 |   200
12/26/2013 |   150
12/25/2013 |   350
12/24/2013 |   450
12/23/2013 |   200
12/22/2013 |   300
12/21/2013 |   100
12/20/2013 |   300

Resulting Table...

DATE       |   7Dayrev
12/31/2013 |    1700 
12/30/2013 |    1950
12/29/2013 |    1850
12/28/2013 |    1750
12/27/2013 |    1750
12/26/2013 |    1850
ETC......

Answer 1

You can do this via correlated subquery:

;WITH cte AS (SELECT *,ROW_NUMBER() OVER(ORDER BY [DATE] DESC) RN
              FROM Table1)
SELECT a.[DATE], a.Revenue, (SELECT SUM(b.Revenue)
                             FROM cte b
                             WHERE b.RN BETWEEN a.RN-6 AND a.RN) as Rev_7Day
FROM   cte a
ORDER BY a.RN DESC 

Demo: SQL Fiddle