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From Damien Katz <>
Subject Re: Bulk Docs
Date Thu, 12 Mar 2009 15:16:46 GMT
Atomic bulk docs is in the patch, it just doesn't do conflict  
checking. If any docs are conflicts, they are saved anyway as  
conflicts. This means it's really for message queue functionality, not  
database consistency, your data is safe and committed but might not be  
immediately available or consistent between docs. The reasons we are  
removing all or nothing with conflict checking as it doesn't work with  
replication (both offline and clustering) as docs are not replicated  
in a single transaction or even in update order. And getting it to  
work with partitioning would cause unacceptable write performances. If  
we leave it, people will rely on the behavior not understanding it  
doesn't really work with the rest of CouchDB.

So if you are currently using bulk docs to guarantee inter-document  
consistency, it already doesn't work with replication. It only works  
on a single machine, so no master-slave and no hot stand-by setup  
would work as neither are guaranteed to be in a consistent state at  
any point.


On Mar 12, 2009, at 8:17 AM, Tim Parkin wrote:

> Hi,
> I noticed a commit that suggests "atomic" bulk docs will no longer be
> working on trunk. Is now the right time to discuss the possibility of
> keeping a version of "atomic" bulk docs somewhere in couchdb rather  
> than
> removing the functionality?
> I think I understand that there is a philosophical reason for not  
> having
> it in (I think the reasoning is "don't have features in couchdb that
> won't work distributed" but I may be wrong ) but I personally am of  
> the
> opinion that trying to hide the difference between a single couchdb  
> and
> network of couchdbs at the cost of removing functionality that has
> legitimate use is not a good idea.
> Anyway - I don't want to start a thread prematurely but also didn't  
> want
> to miss adding my opinion. I'm happy to hang fire on discussion until
> later though..
> Regards
> Tim Parkin

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