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Date: Wed, 20 Nov 2013 22:46:05 +0000
From: Simon Metson <simon@cloudant.com>
To: user@couchdb.apache.org
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Subject: Re: Considering CouchDB
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Nope, views are updated on read, hence the "blocking" behaviour you describe. You can query with update_after, which returns the stale index then triggers the update.  


On Wednesday, 20 November 2013 at 22:43, Mark Hahn wrote:

> I thought that every write triggered a view rebuild and that the stale
> option only meant a read didn't have to wait for a current rebuild to
> finish. That would means the views are pretty much up-to-date.
> 
> 
> On Wed, Nov 20, 2013 at 2:36 PM, Robert Newson <rnewson@apache.org> wrote:
> 
> > True, but remember couchdb doesn't automatically keep indexes fresh in
> > the background, so "stale" can be "really really stale". ;)
> > 
> > B.
> > 
> > 
> > On 20 November 2013 22:34, Simon Metson <simon@cloudant.com> wrote:
> > > Unless your app can deal with querying the view stale.
> > > 
> > > 
> > > On Wednesday, 20 November 2013 at 21:56, Mark Hahn wrote:
> > > 
> > > > I meant http view requests were blocked. It is waiting for the view
> > > > rebuild.
> > > > 
> > > > I'm can't type what I'm thinking today.
> > > > 
> > > > 
> > > > On Wed, Nov 20, 2013 at 1:54 PM, Mark Hahn <mark@reevuit.com> wrote:
> > > > 
> > > > > never mind. I wasn't talking about the file level at all. I meant that
> > > > > http read requests are blocked after http update requests.
> > > > > 
> > > > > 
> > > > > On Wed, Nov 20, 2013 at 1:52 PM, Robert Newson <rnewson@apache.org>
> > wrote:
> > > > > 
> > > > > > "DB reads are blocked by DB updates at the http level."
> > > > > > 
> > > > > > Nope, there's a process that can read the database and a separate
> > one
> > > > > > for writing to it. Writing to an append only file is obviously
> > > > > > serialized but there's no need to block reads.
> > > > > > 
> > > > > > B.
> > > > > > 
> > > > > > 
> > > > > > On 20 November 2013 21:35, Mark Hahn <mark@reevuit.com> wrote:
> > > > > > > > Database writes are not coupled to view updates.
> > > > > > > 
> > > > > > > 
> > > > > > > 
> > > > > > > I understand now, you are talking about file read/write level. DB
> > reads
> > > > > > > are blocked by DB updates at the http level.
> > > > > > > 
> > > > > > > 
> > > > > > > On Wed, Nov 20, 2013 at 1:05 PM, Robert Newson <
> > robert.newson@gmail.com
> > > > > > > wrote:
> > > > > > > 
> > > > > > > > "A write requires updating views and reads have to wait for the
> > update"
> > > > > > > > 
> > > > > > > > Is not true. Database writes are not coupled to view updates.
> > > > > > > > 
> > > > > > > > Sent from my iPad
> > > > > > > > 
> > > > > > > > > On 20 Nov 2013, at 20:59, Mark Hahn <mark@reevuit.com> wrote:
> > > > > > > > > 
> > > > > > > > > A write requires updating views and reads have
> > > > > > > > > to wait for the update
> > > > > > > > > 
> > > > > > > > 
> > > > > > > > 
> > > > > > > 
> > > > > > 
> > > > > 
> > > > 
> > > 
> > 
> > 
> 
> 
> 


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