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From AJ ...@dude.podzone.net>
Subject Re: Storing Accounting Data
Date Wed, 22 Jun 2011 02:58:55 GMT
On 6/21/2011 3:36 PM, Stephen Connolly wrote:
>
> writes are not atomic.
>
> the first side can succeed at quorum, and the second side can fail 
> completely... you'll know it failed, but now what... you retry, still 
> failed... erh I'll store it somewhere and retry it later... where do I 
> store it?
>
> the consistency level is about tuning whether reads and writes are 
> replicated/checked across multiple of the replicates... but at any 
> consistency level, each write will either succeed or fail _independently_
>
> you could have one column family which is kind of like a transaction 
> log, you write a json object of all the mutations you will make, then 
> you go and make the mutations, when they succeed you write a completed 
> column to the transaction log... them you can repeat that as often as need
>
> you could have transactions posted as columns in a row, and to get the 
> balance you iterate all the columns adding the +'s and -'s
>
> by processing the transaction log, you could establish the highest 
> complete timestamp, and add summary balance columns being the running 
> total up to that point, so that you don't have to iterate everything
>
> - Stephen
>

Yeah, it's all more than I want to do.  But, I just rediscovered 
Dominic's Cages <http://code.google.com/p/cages/>.   Has anyone tried it?
>
> ---
> Sent from my Android phone, so random spelling mistakes, random 
> nonsense words and other nonsense are a direct result of using swype 
> to type on the screen
>
> On 21 Jun 2011 22:04, "AJ" <aj@dude.podzone.net 
> <mailto:aj@dude.podzone.net>> wrote:


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