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Accumulo >> mail # user >> Reverse timestamp order?


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Mike Hugo 2013-02-15, 23:05
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Josh Elser 2013-02-16, 01:44
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Aaron Cordova 2013-02-16, 00:38
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Re: Reverse timestamp order?
On a related note, it would be cool to have the ability to reverse the
sorting order completely, basically reading the map files in reverse. There
might be some issues with iterator to make data 'look' right but it would
be cool to be able to scan back and fourth on tables while generating
visualizations, etc.
On Feb 15, 2013 7:38 PM, "Aaron Cordova" <[EMAIL PROTECTED]> wrote:

> Mike,
>
> There is no built in way to do this. If you are replaying history more
> often than you are grabbing the latest version, you may consider
> time-stamping the keys yourself with MAX_LONG - current system time in your
> ingest client.
>
> If you want to grab the whole list and resort, the WholeRowIterator makes
> it easy to grab a whole rows worth of data at once, assuming your rows fit
> in memory.
>
> Sent from my iPad
>
> On Feb 15, 2013, at 6:05 PM, Mike Hugo <[EMAIL PROTECTED]> wrote:
>
> > When iterating over multiple versions of the same key, is there a way to
> receive them in chronological order rather than last inserted first?
> >
> > For example, if I insert
> >
> > aKey cf1 cq1 10 aValue1
> > aKey cf1 cq1 20 aValue2
> > aKey cf1 cq1 30 aValue3
> >
> > When scanning I receive them in reverse timestamp order - which is great
> for retrieving the most recent version
> >
> > aKey cf1 cq1 30 aValue3
> > aKey cf1 cq1 20 aValue2
> > aKey cf1 cq1 10 aValue1
> >
> > If I'd like to "replay" history, should I basically grab the whole list
> and then invert it, or is there a built in way to do this?
> >
> > Thanks!
> >
> > Mike
> >
>
NEW: Monitor These Apps!
elasticsearch, apache solr, apache hbase, hadoop, redis, casssandra, amazon cloudwatch, mysql, memcached, apache kafka, apache zookeeper, apache storm, ubuntu, centOS, red hat, debian, puppet labs, java, senseiDB