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" <a...@dude.podzone.net
<mailto:a...@dude.podzone.net>> wrote: