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From "Hiller, Dean" <>
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.


On 12/11/12 9:46 AM, "Ayush V." <> wrote:

>I'm working on Cassandra Hadoop intergration (MapReduce). We have used
>Partioner to insert data to gain faster write. Now we have to read that
>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
>of the RowKey)? 
>Does using secondary indexes (still trying to understand how it works)
>solve my problem or is there some other way around?
>I will be really appreciated if someone could answer my queries.
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