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From: Sylvain Lebresne <sylvain@yakaz.com>
Date: Tue, 15 Jun 2010 12:06:30 +0200
Message-ID: <AANLkTikK6H51LhbqAcVLBMS5qZslxTkpADL7x8Xy-p0O@mail.gmail.com>
Subject: Re: How to get previous / next data?
To: user@cassandra.apache.org
Cc: bram.vanderwaaij@tno.nl
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You want to use 'reversed' in SliceRange (and a start with whatever
you want and a count of 2).

--
Sylvain

On Tue, Jun 15, 2010 at 12:01 PM, Bram van der Waaij
<bramattno@gmail.com> wrote:
> Hello,
>
> We want to use cassandra to store and retrieve time related data. Storing
> the time-value pairs is easy and works perfectly. The problem arrives at
> retrieving the data. We do not only want to retrieve data from within a time
> range, but also be able to get the previous and/or next data sample from a
> specific point in time.
>
> The next in time i can retrieve by giving asking for the range
> timestamp...maxtime and request for 2 items. Which returns timestamp (if
> available) and the next timestamp-value.
>
> Does anybody know how i can retrieve the previous timestamp? The columns are
> sorted on the key(timestamp), so the previous request/next should not be a
> difficult to perform.
>
> Any suggestions are welcome!
>
> Thanks,
>
> Bram van der Waaij