replication order

[Ryan Hiebert <ry...@ryanhiebert.com>]

When replication is being done, in what order will the changes be applied?  In the order that they happened, or in the order of the _id they refer to, or some other ordering, or is there no ordering that can be expected.  For instance, if I move a document, I would like to make sure that I never have two versions of the document.  To this end, I first delete the document, and then create it again with the new _id.  In a replicated database, can I be sure that the document will be first deleted, and then created on the replicated database?

Thanks,

Ryan

Re: replication order

[Ryan Hiebert <ry...@ryanhiebert.com>]

The main thing I was worried about is that the changes would be applied in replication in the order that I made them (assuming I made the changes from one node).  In our case, we associate IP address documents that contain DNS host information.  We'd like to make sure that a dns hostname is only ever associated with the correct IP address, so that when I move the dns hostname from from one IP address document to another, I can be sure that if it shows up in the new document, it is NOT in the old one.

I know that perhaps a more preferred way of making sure non-duplicity would be to make dns documents instead, but that constraint is not universal.  Sometimes I do want multiple IP addresses for a domain.  Just sometimes I don't, and I want to make sure that change can be counted on happening the way that I've done it.

On May 18, 2011, at 6:28 PM, Sean Copenhaver wrote:

> I'm curious why are you worried about multiple revisions of a document?
> 
> 
> 
> On May 18, 2011, at 7:20 PM, Paul Davis <pa...@gmail.com> wrote:
> 
>> On Wed, May 18, 2011 at 7:08 PM, Ryan Hiebert <ry...@ryanhiebert.com> wrote:
>>> When replication is being done, in what order will the changes be applied?  In the order that they happened, or in the order of the _id they refer to, or some other ordering, or is there no ordering that can be expected.  For instance, if I move a document, I would like to make sure that I never have two versions of the document.  To this end, I first delete the document, and then create it again with the new _id.  In a replicated database, can I be sure that the document will be first deleted, and then created on the replicated database?
>>> 
>>> Thanks,
>>> 
>>> Ryan
>> 
>> The updates are applied in the order of the update sequence. You can
>> view that sequence using the changes feed. Your proposed scenario is
>> listed under "assuming those are the only two edits applied to those
>> two docs in any database that ever replicates with your network of
>> dbs, then yes".

Re: replication order

[Sean Copenhaver <se...@gmail.com>]

I'm curious why are you worried about multiple revisions of a document?



On May 18, 2011, at 7:20 PM, Paul Davis <pa...@gmail.com> wrote:

> On Wed, May 18, 2011 at 7:08 PM, Ryan Hiebert <ry...@ryanhiebert.com> wrote:
>> When replication is being done, in what order will the changes be applied?  In the order that they happened, or in the order of the _id they refer to, or some other ordering, or is there no ordering that can be expected.  For instance, if I move a document, I would like to make sure that I never have two versions of the document.  To this end, I first delete the document, and then create it again with the new _id.  In a replicated database, can I be sure that the document will be first deleted, and then created on the replicated database?
>> 
>> Thanks,
>> 
>> Ryan
> 
> The updates are applied in the order of the update sequence. You can
> view that sequence using the changes feed. Your proposed scenario is
> listed under "assuming those are the only two edits applied to those
> two docs in any database that ever replicates with your network of
> dbs, then yes".

Re: replication order

[Paul Davis <pa...@gmail.com>]

On Wed, May 18, 2011 at 7:08 PM, Ryan Hiebert <ry...@ryanhiebert.com> wrote:
> When replication is being done, in what order will the changes be applied?  In the order that they happened, or in the order of the _id they refer to, or some other ordering, or is there no ordering that can be expected.  For instance, if I move a document, I would like to make sure that I never have two versions of the document.  To this end, I first delete the document, and then create it again with the new _id.  In a replicated database, can I be sure that the document will be first deleted, and then created on the replicated database?
>
> Thanks,
>
> Ryan

The updates are applied in the order of the update sequence. You can
view that sequence using the changes feed. Your proposed scenario is
listed under "assuming those are the only two edits applied to those
two docs in any database that ever replicates with your network of
dbs, then yes".