Re: Aggregates: Largest Groups

From: David Fetter <david_at_fetter.org>
Date: Mon, 22 Mar 2010 16:12:50 -0500
Message-ID: <uqednXVve-PPQDrWnZ2dnUVZ_oWdnZ2d_at_speakeasy.net>



Gene Wirchenko <genew_at_ocis.net> wrote:
> On Mon, 22 Mar 2010 15:42:09 -0500, david_at_fetter.org (David Fetter)
> wrote:
> 

>>Let's say I have a traffic monitoring system. The stream of data
>>coming in records a timestamp and a speed for each vehicle.
>>
>>I'd like to know what all the groups of vehicles larger than X whose
>>with average speed over Y is.
>>
>>Any ideas how to approach this?
> 
>     First, define your terms.  What is a group?  What does "larger
> than X" mean?  (Size of vehicle?  Number of vehicles in the group?)

Number of vehicles in the group.

Cheers,
David.

-- 
David Fetter <david_at_fetter.org> http://fetter.org/
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Received on Mon Mar 22 2010 - 16:12:50 CDT

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