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	 <e2111bbb0908250739p14ec22cbx26827c089875ae4b@mail.gmail.com>
Date: Tue, 25 Aug 2009 11:17:17 -0700
Message-ID: <e8d26ac40908251117y65b8a762s93c9791be6a9ba49@mail.gmail.com>
Subject: Re: Referential Integrity with Unique IDs
From: Adam Wolff <awolff@gmail.com>
To: user@couchdb.apache.org
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I thought the point of uuids was that you could just make one up and assume
that it's unique.
A

On Tue, Aug 25, 2009 at 7:39 AM, Paul Davis <paul.joseph.davis@gmail.com>wrote:

> The only way to make absolutely certaint that something is unique is
> to include it in the document id in some fashion.
>
> I generally solve this with sha1's for docids and then reference those
> ids from the doc. Depending on the size of your unique value, it may
> be beneficial to include a copy inline.
>
> HTH,
> Paul Davis
>
> On Tue, Aug 25, 2009 at 10:21 AM, Jan Vincent
> Liwanag<jvliwanag@gmail.com> wrote:
> > Hi guys,
> >
> > For some document type, I have some property 'x' which I'd like to be
> unique
> > across all records. However, the value for this property may change.
> >
> > The way I see it is that I have two options. If I derive the id from this
> > property 'x', then I am assured of its uniqueness. However, I cannot
> easily
> > change the value for property 'x', as the value of the id depends on it.
> > Moreover, I may have to update all records which refers to it.
> >
> > If I use a uuid however, referential integrity is retained. However, I'm
> not
> > sure if CouchDB alone can make sure that the value for that property is
> > unique.
> >
> > Any thoughts on this?
> >
> > Thanks,
> >
> > JV Liwanag
> >
>

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