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From Chris Mawata <chris.maw...@gmail.com>
Subject Re: what all can be done using MR
Date Sat, 11 Jan 2014 16:16:29 GMT
Results will be sorted by key so make A the key and put the rest in the
value
Chris
On Jan 11, 2014 10:11 AM, "unmesha sreeveni" <unmeshabiju@gmail.com> wrote:

> 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 <chris.mawata@gmail.com>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/
>
>
>

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