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Date: Tue, 6 Nov 2012 17:33:28 +0400
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Subject: Re: Any sort order guarantee for key (value) argument of CouchDB
 reduce function?
From: Vladislav Ponomarev <ponomarevvlad@gmail.com>
To: user@couchdb.apache.org
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Thank you Paul.

This is odd to me, but I'll live with that :-)

On Tue, Nov 6, 2012 at 5:05 PM, Paul J Davis <paul.joseph.davis@gmail.com>wrote:

> No, there aren't any guarantees. And rereduce can end up getting passed
> some surprising (to me when I tried relying on ordering at least) sets of
> keys.
>
> On Nov 6, 2012, at 1:55 PM, Vladislav Ponomarev <ponomarevvlad@gmail.com>
> wrote:
>
> > Hello,
> >
> > Per CouchDB guide, the reduce function signature looks like this:
> >
> > function (key, values, rereduce) {
> >    return ...; // some calculations happen here
> > }
> >
> > where the definition of first arguments is as follows:
> >
> >>
> >> when rereduce is false, then:
> >>
> >>   - key will be an array whose elements are arrays of the form [key,id],
> >>   where key is a key emitted by the map function and id is that of the
> >>   document from which the key was generated.
> >>   - values will be an array of the values emitted for the respective
> >>   elements in keys.
> > My question is: when rereduce is false, are there any guarantees
> regarding
> > the order of key (or values) array elements? My gut feel (based on Reduce
> > vs Rereduce chapter) is that keys, and respectively values, should be
> > ordered, but I do not see any direct confirmation.
> >
> > Any ideas? Thank you!
>

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