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Date: Mon, 17 Mar 2008 14:26:48 +0000
From: Alan Bell <alan@theopenlearningcentre.com>
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To: couchdb-user@incubator.apache.org
Subject: Re: Relying on revisions for rollbacks
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Could the compaction mechanism be rules based? For example it could run 
a javascript function like a view function passing in the document 
object and revision id and the function would return true or false 
depending on whether it is OK to purge that version. I can imagine some 
use cases where revisions would never be archived, others where 
revisions might be kept for 6 months, others where the last 5 revisions 
are kept regardless of age. More complex options might be possible, such 
as retaining every third revision older than 6 months or in a wiki 
context purging edits marked as minor.

Alan.

Jan Lehnardt wrote:
> Heya,
> On Mar 17, 2008, at 7:29 , Shahar Evron wrote:
>> [...]
>> As far as I understood, CouchDB does not keep old revisions indefinitely
>> - so if I update a document, it's previous revisions might be deleted
>> after a while.
>>
>> Is this true?
>
> That is correct. Not at the moment though :) The next release of CouchDB
> will include a mechanism called "compaction" that will run 
> periodically and
> prune out old revisions.
>
> We suggest that you manage old revisions to a document that you want
> to keep around in attachments to the latest revision.
>
> Cheers
> Jan
> -- 


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Alan Bell
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