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From "Hiller, Dean" <Dean.Hil...@nrel.gov>
Subject Re: Filter data on row key in Cassandra Hadoop's Random Partitioner
Date Tue, 11 Dec 2012 18:22:29 GMT
You may want to look into CQL3 as I hear there may be a way to specify the
query so only those rows are map/reduced.  I am not sure if that is out
yet or not but I remember someone from datastax telling me about it.

Dean

On 12/11/12 9:46 AM, "Ayush V." <ayushv.av@gmail.com> wrote:

>I'm working on Cassandra Hadoop intergration (MapReduce). We have used
>Random
>Partioner to insert data to gain faster write. Now we have to read that
>data
>from cassandra in MapReduce and perform some calculation on it.
>
>From the lots of data we have in cassandra we wan't to fetch data only for
>particular ROW-KEYs but we are unable to do it due to RandomPartioner -
>assertion is there in code.
>
>Can anyone please guide me how should I filter data based on RowKey on
>Cassandra level itself (I know data is distributed across regions using
>Hash
>of the RowKey)? 
>
>Does using secondary indexes (still trying to understand how it works)
>will
>solve my problem or is there some other way around?
>
>I will be really appreciated if someone could answer my queries.
>
>Thanks 
>AV
>
>
>
>--
>View this message in context:
>http://cassandra-user-incubator-apache-org.3065146.n2.nabble.com/Filter-da
>ta-on-row-key-in-Cassandra-Hadoop-s-Random-Partitioner-tp7584212.html
>Sent from the cassandra-user@incubator.apache.org mailing list archive at
>Nabble.com.


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