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From Stanley Iriele <siriele...@gmail.com>
Subject Re: Considering CouchDB
Date Wed, 20 Nov 2013 23:18:19 GMT
Yeah..it seems that way...but Imagine a scenario where there are a lot of
writes... But few reads... Like...tracking user installs...and queries that
occasionally need to see the number of installs... Unless that query is
being run often... It will fall behind and anyone waiting for it to reindex
won't be very happy. update after doesn't solve that ..so a HEAD every
request every minute or so keeps it relatively up to date.... So you
guarantee the client won't wait too long...Sven of they haven't made a read
request in a while
On Nov 20, 2013 3:01 PM, "Mark Hahn" <mark@hahnca.com> wrote:

> > .it sounds hackey.
>
> Just use update_after.  It's not a hack.
>
>
> On Wed, Nov 20, 2013 at 2:59 PM, Stanley Iriele <siriele2x3@gmail.com
> >wrote:
>
> > Idk..it sounds hackey.. But curl and crontab is good enough for me for
> the
> > views that can't fall more than 1 minute behind
> > On Nov 20, 2013 2:57 PM, "Robert Newson" <rnewson@apache.org> wrote:
> >
> > > The bigcouch merge will not bring any automatic view updating
> > > scheduler. Nothing stops someone contributing one, of course.
> > >
> > > B.
> > >
> > >
> > > On 20 November 2013 22:49, Mike Marino <mmarino@gmail.com> wrote:
> > > > There are, of course, ways to get couchdb to update views dependent
> on
> > > > writes. I also believe this is supposed to get easier in the future
> > > > (included in the bigcouch merge?).
> > > >
> > > >> Am 20.11.2013 um 23:46 schrieb Simon Metson <simon@cloudant.com>:
> > > >>
> > > >> 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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