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From: Zachary Zolton <zachary.zolton@gmail.com>
Date: Wed, 24 Mar 2010 15:09:09 -0500
Message-ID: <f728979f1003241309t75f2502eh5be2dfc6575e060@mail.gmail.com>
Subject: Re: group_level in reduce function
To: user@couchdb.apache.org
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Folks who really need to chain map-reduced views have to hand-roll
their own solution. This usually involve some scripting to keep a
derived database up-to-date with the output of the source database's
view.


On Wed, Mar 24, 2010 at 2:20 PM, Aur=E9lien B=E9nel <aurelien.benel@utt.fr>=
 wrote:
> Thanks for your answer.
>
>> If you want to be able to be able to include the same piece of code in m=
ultiple views
> Good idea, I'll do that.
>
>> What do you mean by a script to "combine several views"?
> I mean that the implementations of algorithms that benefit from MapReduce=
 (TF.IDF, Markov chains, K nearest neighbors...) usually need to chain seve=
ral MapReduces: =A0the input of a map/reduce is generated by others. I stil=
l don't know how to do that in CouchDB.
>
>
> Regards,
>
> Aur=E9lien