On 02/24/2011 06:20 PM, Josh Berkus wrote:
> SELECT id_key, time_stamp, value
> FROM (
> SELECT id_key, time_stamp, value,
> row_number()
> OVER ( PARTITION BY id_key
> ORDER BY time_stamp DESC)
> as ranking
> FROM thetable
> ) as filtered_table
> WHERE ranking = 1
Why did you use row_number instead of rank?
I am now curious how the speed compares though. I still think the
DISTINCT ON will be faster, but it would be a great surprise.
--
Shaun Thomas
OptionsHouse | 141 W. Jackson Blvd. | Suite 800 | Chicago IL, 60604
312-676-8870
sthomas@peak6.com
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