How can I sum the last 15 rows in my database table?

Question

I have a sales table with the following columns:

Now I want to SUM

update the last 15 lines, so I'm currently doing:

SELECT TOP 15 SUM(amount) FROM Sales ORDER BY [Date] DESC

But I get 15 lines, obviously there is a way I can sum it up and no need to iterate over and SUM it on the client side?

0

Blankman May 25 '09 at 14:53

2 answers

SELECT Sum(amount )
FROM
(
   SELECT Top 15 amount FROM Sales ORDER BY [Date] Desc
) as bar

+3

Eoin campbell May 25 '09 at 14:56

gbn · Accepted Answer · 2009-05-25T14:54:46+0000

SELECT
    SUM (Amount)
FROM
    (SELECT TOP 15 amount FROM Sales ORDER BY [Date] DESC) foo