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Date: Wed, 17 Nov 2010 17:14:33 -0800
Message-ID: <AANLkTi=jP=1GcR7PeE-bWOZmxLH6Xn2rJ9DG_BvCrYTD@mail.gmail.com>
Subject: Re: Write race conditions, working without _rev
From: Randall Leeds <randall.leeds@gmail.com>
To: user@couchdb.apache.org
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On Wed, Nov 17, 2010 at 16:15, Chad George <chad@mgproducts.com> wrote:
> I've been wondering about this for a while, when two update requests for the
> same document come to couchdb nearly simultaneously what exactly happens?
>
> Is it possible for both requests to get the same revision of the document to
> update or is there some mechanism to force the updates to occur in series?
>

There is a mechanism. The message passing within the Erlang runtime
guarantee an ordering of messages to the update process.
It is impossible for both updates to occur.