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From faust 1111 <faust...@gmail.com>
Subject Re: About denormalization and keep consistent
Date Fri, 09 Apr 2010 23:56:40 GMT
In my case
change of author name is exceptional situation.
its happen rarely.


I think  i can do like this:
  when author change name
  i create doc mark that i begin update all related contents
  then  try update
  then remove mark

if update is fail(mark not reomve), i will know about and can continue.

And i think i don't need  run backend process listen
_changes feed i can  catch changes in my app model Author.


2010/4/10 Michael Ludwig <milu71@gmx.de>:
> Andrew Melo schrieb am 09.04.2010 um 15:04:59 (-0500)
> [Re: About denormalization and keep consistent]:
>
>> > Are there scenarios where writing happens to an SQL server, from
>> > where NoSQL replicas are fed and used to serve readers?
>>
>> Possibly. But, if you're writing to a single SQL master, then you lose
>> two benefits of Couch: horizontally scalable writes and not having to
>> be restricted by SQL's data model. You could do (for instance) single
>> master writes and many-slave reads on a stock SQL server in that case.
>
> Thanks, Andrew. It appears Faust is concerned about data consistency
> which is usually and easily ensured by suitable SQL data modeling. That
> does not happen to be the forte of a system designed for scalability at
> the expense of consistency.
>
> Faust, there are many places and cases where data can be copied and held
> redundantly in hundreds or thousands of places, and it simply doesn't
> matter. Think email, for example. If you changed the name belonging to
> your email address to "Johann Faust", it wouldn't matter that there are
> mails with the older version of your name in the archive, and they
> wouldn't have to be updated, and they even shouldn't be updated. That
> seems to be an excellent use case for a system like CouchDB.
>
> If, on the other hand, you care about consistency in the way you
> described, you might want to consider using a system that supports
> you in guaranteeing such consistency.
>
> --
> Michael Ludwig
>

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