SQL Server 2008 using SUM() OVER(ORDER BY...)
I am trying to use a CTE and CROSS JOIN the result set. I want to sum up the 4 rows leading up to the current row. The example online I found does not use a CTE, only a newly created table (http://sqlandme.com/2011/08/17/sql-server-denali-over-rows-range/). The syntax should work, but I get an error saying "Incorrect syntax near 'ROWS'".
An Example output would be this using the following statement: SUM(y) OVER(ORDER BY x ROWS 4 PRECEDING) sum
X Y SUM
1 7 0 No prev rows, so sum is 0
2 1 7 Sum = 7
3 2 8 = 1 + 7
4 5 10 = 2 + 1 + 7
5 7 15 = 5 + 2 + 1 + 7
6 34 15 = 7 + 5 + 2 + 1
7 32 48 开发者_开发百科 = 34 + 7 + 5 + 2
Does anyone have any suggestion on what is incorrect with the query? Thanks in advance.
with quarterResults as (
<subquery in here>
)
--COLUMN1: String
--COLUMN2: Date
--COLUMN3: Date
--COLUMN4: Double
select a.TIC, a.DATADATE, a.EFFDATE, SUM(b.valuei) OVER (ORDER BY a.TIC, a.DATADATE, a.EFFDATE ROWS 4 PRECEDING) AS [SUM]
from quarterResults a
cross join quarterResults b
where a.datadate > b.datadate
group by a.tic, a.datadate, a.EFFDATE, a.valuei
order by a.TIC, a.datadate
The documentation you found for ROWS/RANGE is not for SQL Server 2008 - it's for a future version of SQL Server.
To accomplish your query in SQL 2008, one approach would be similar to:
SELECT a.TIC, a.datadate, a.effdate, x.s
FROM quarterResults a
CROSS APPLY ( SELECT ISNULL(SUM(v), 0)
FROM ( SELECT TOP(4) b.valuei
FROM quarterResults b
WHERE b.datadate < a.datadate
ORDER BY b.datadate DESC ) x(v)
) x(s)
ORDER BY a.TIC, a.datadate
Note that this is potentially an expensive query. The use of the OVER expression with ROWS would probably be more efficient but, again, it is not available in SQL Server 2008.
You tagged SQL Server 2008.
The syntax isn't ready until next release SQL Server 2012 aka Denali
精彩评论