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Message-ID: <4DA3452F.5050809@mage.hu>
Date: Mon, 11 Apr 2011 20:15:11 +0200
From: Mage <mage@mage.hu>
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To: Owen Marshall <omarshall@facilityone.com>
CC: user@couchdb.apache.org
Subject: Re: replication
References: <4DA1A9CC.4070407@mage.hu> <4DA32E5C.6090100@facilityone.com>
 <4DA33815.5000303@mage.hu> <4DA33DBA.1070500@facilityone.com>
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Conflicts will occur any time that edits diverge. It's possible for
> conflicts to occur on replication:
>
> * Nodes B & C pull document 1 from node A
> * Nodes B & C make & save separate changes to document 1
> * Replication occurs, either between B & C, or from one node to A and
> then to the other.
>
> Note that continuous replication reduces the time window for conflicts
> to occur, but it will not eliminate them. Thus you must treat conflicts
> not as an "exceptional case" but as an expected state.

I could not trigger conflict straight by the replication. I mean that
one version of the document just totally lost when I started the
replication.

Steps:

Node A            Node B
Version 1         Version 1
Version 2-A       Version 1
Version 2-A       Version 2-B
...replication...
Version 2-B       Version 2-B


If I, for example, open two browser windows for the same document on
same database, conflict can happen: I start editing in the first window,
I start editing in the second, I save the second then I save the first.
Conflict happens. This is fair and clear situation.

However if I do the same with two nodes (databases) and I start
replication after the modifying I just lose one version of the document.
On both nodes.

        Mage