Mailing-List: contact user-help@couchdb.apache.org; run by ezmlm
Precedence: bulk
Reply-To: user@couchdb.apache.org
Content-Type: text/plain; charset=iso-8859-1
Mime-Version: 1.0 (Mac OS X Mail 7.1 \(1827\))
Subject: Re: CouchDB transactions?
From: Robert Samuel Newson <rnewson@apache.org>
In-Reply-To: 
 <CAK0S_BBfY=cBmWnewA3LJvYbBj4sHVuX2br=s0La_XD4bNAcZg@mail.gmail.com>
Date: Thu, 6 Feb 2014 23:13:48 +0000
Content-Transfer-Encoding: quoted-printable
Message-Id: <F3E8F0D4-D9B8-44ED-BAD5-7329511F2E59@apache.org>
References: 
 <CADHK3SBwUMHH-M+Yoeh74rw5KZONukCEn4-FvZDfYZ8BZZyXnw@mail.gmail.com>
 <CADHK3SCFcUkGOmqS5SLN8QrHC+wV2_s3_Lrz7VwEV7UGD42oGg@mail.gmail.com>
 <52F40F9E.6040105@alwaysreformed.com>
 <CAK0S_BBfY=cBmWnewA3LJvYbBj4sHVuX2br=s0La_XD4bNAcZg@mail.gmail.com>
To: user <user@couchdb.apache.org>


CouchDB transactions are at the individual document level, _bulk_docs =
are *not* atomic at the group level with any settings.

B.

On 6 Feb 2014, at 23:01, Mark Hahn <mark@hahnca.com> wrote:

> That doesn't guarantee a real transaction though, does it?  Two of =
these
> could overlap.
>=20
> Also: "If the _rev does not match the current version of the document, =
then
> that particular document will *not* be saved ..."
>=20
> Since you can't prevent collisions this would seem to be a =
show-stopper.
>=20
>=20
> On Thu, Feb 6, 2014 at 2:41 PM, Tim Black <tim@alwaysreformed.com> =
wrote:
>=20
>>=20
>> On 02/06/2014 04:07 PM, Jo-Erlend Schinstad wrote:
>>> A while ago (a year or so) I tried to use CouchDB to model trees. =
This
>>> worked fine, except inserting or moving nodes proved very difficult, =
if
>> not
>>> impossible. The reason was that when I wanted to a move or insert, =
that
>>> meant updating prev_node on two different documents. If something
>> happened
>>> after the first document was updated and before the second was =
updated,
>> it
>>> would mean the tree would be completely broken.
>>>=20
>>> If I could get a guarantee that these two documents were updated
>>> simultaneous or not at all, both in the local database and while
>>> replicating, I believe all my problems would be fixed. And I would
>>> absolutely love this, because I was able to do some pretty cool =
things in
>>> my prototypes.
>>>=20
>>> So; is this possible now or will it be? Just to be clear; I'm not =
asking
>>> for relationships between documents, but merely a guarantee that a =
group
>> of
>>> documents are updated simultaneously or not at all.
>> I need to do the same thing.  Would bulk updates solve the problem =
for you?
>>=20
>>=20
>> =
http://wiki.apache.org/couchdb/HTTP_Bulk_Document_API#Modify_Multiple_Docu=
ments_With_a_Single_Request
>>=20
>> Tim
>>=20
>>=20