Re: Sum of multiplied deltas

Any hints for an 8.3 environment (currently)?

Thnx.

Ciao,
Gerhard

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http://www.wiesinger.com/

On Mon, 8 Jun 2009, David Fetter wrote:

> On Mon, Jun 08, 2009 at 08:35:20AM +0200, Gerhard Wiesinger wrote:
>> Hello!
>>
>> I've the following data:
>> datetime | val1 | val2
>> time1 | 4 | 40%
>> time2 | 7 | 30%
>> time3 | 12 | 20%
>> ...
>>
>> I'd like to sum up the following:
>>
>> (7-4)*30% + (12-7)*20% + ...
>
> This is best done in 8.4 using Windowing. Sadly, it's an 8.4-only
> feature, and dodgy hacks are the rule until you can use them.
>
> Cheers,
> David.
>>
>> datetime is ordered (and unique and has also an id).
>>
>> Rows are in the area of millions.
>>
>> How is it done best?
>> 1.) Self join with one row shift?
>> 2.) function?
>>
>> Any hint?
>>
>> Thnx.
>>
>> Ciao,
>> Gerhard
>>
>> --
>> http://www.wiesinger.com/
>>
>>
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