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Message-ID: <e2111bbb0812280707n1b12bf9dg5ae3b9081b65c30b@mail.gmail.com>
Date: Sun, 28 Dec 2008 10:07:21 -0500
From: "Paul Davis" <paul.joseph.davis@gmail.com>
To: user@couchdb.apache.org
Subject: Re: newbie question #1
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On Sun, Dec 28, 2008 at 9:54 AM, Geir Magnusson Jr. <geir@pobox.com> wrote:
>
> On Dec 28, 2008, at 9:36 AM, Paul Davis wrote:
>
>> [snip]
>>>
>>> I read the view docs (and have other questions there, like if the M/R is
>>> distributed across a cluster - I've used M/R w/ Hadoop, so I come w/ a
>>> set
>>> of assumptions...)  and I saw that it doesn't *appear* that the key or id
>>> is
>>> injected in the view doc, which of course brings up an obvious question
>>> :)
>>
>> The CouchDB implementation of Map/Reduce (specifically reduce) is a
>> bit different the the canonical implementation. Mostly this is a
>> result of being stored in a btree and Damien's cleverness.
>>
>
> Does the work get distributed across nodes, or does each node do the same
> thing?
>

Oh sorry, I totally meant to answer that question in my earlier reply.

No. Not yet. IIRC, the current rough sketch of a design is that
CouchDB will be able to do automatic sharding of a single database,
and each node would be responsible for building a view of its
particular shard. Then at  query time you just have a big merge sort
type of operation.

> geir
>
>