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HDFS, mail # user - Re: what all can be done using MR


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Re: what all can be done using MR
unmesha sreeveni 2014-01-11, 15:10
What about sorting .
Acutually it is done by MapReduce itself.
But if we are giving a csv file as input and trying to sort one/multiple
column...Whether the corresponting columns also get reflectted??

eg: foo.csv
 B,2,3
A,4,6

When we apply sorting to first column:whether the resultent will be
A,4,6
B,2,3
A will be mapped to its correct values right?
If so what will be context.write() of mapper?
On Wed, Jan 8, 2014 at 8:18 PM, Chris Mawata <[EMAIL PROTECTED]> wrote:

>  Yes.
> Check out, for example,
> http://packtlib.packtpub.com/library/hadoop-mapreduce-cookbook/ch06lvl1sec66#
>
>
>
> On 1/8/2014 2:41 AM, unmesha sreeveni wrote:
>
>  Can we do aggregation with in Hadoop MR
> like find min,max,sum,avg of a column in a csv file.
>
>  --
> *Thanks & Regards*
>
>  Unmesha Sreeveni U.B
>  Junior Developer
>
>  http://www.unmeshasreeveni.blogspot.in/
>
>
>
>
--
*Thanks & Regards*

Unmesha Sreeveni U.B
Junior Developer

http://www.unmeshasreeveni.blogspot.in/