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MapReduce, mail # user - Find max and min of a column in a csvfile


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Re: Find max and min of a column in a csvfile
unmesha sreeveni 2014-01-11, 15:04
Thanks Jiayu and John Hancock.
Showered a very nice hint for me.

John that was a really gud link you provided. But i dnt know Pig. I am
using java.
Is there any java related  document.
like :
http://packtlib.packtpub.com/library/hadoop-mapreduce-cookbook/ch06lvl1sec66#
On Sat, Jan 11, 2014 at 6:14 PM, John Hancock <[EMAIL PROTECTED]>wrote:

> Unmesha,
>
> You may want to write your own mapper and reducer for the purpose of
> learning more about map-reduce programming techniques.
>
> However, the Pig documentation also discusses aggregate functions such as
> max() which may save you some time:
>
> http://pig.apache.org/docs/r0.12.0/udf.html
>
>
> -John
>
>
> On Fri, Jan 10, 2014 at 12:23 PM, Jiayu Ji <[EMAIL PROTECTED]> wrote:
>
>> if you are doing with only one column, then I think the key/value pair
>> could be Null and number( elements) . If you are doing more than one
>> column, then column name and numbers.
>>
>>
>> On Fri, Jan 10, 2014 at 12:36 AM, unmesha sreeveni <[EMAIL PROTECTED]
>> > wrote:
>>
>>>
>>> Need help
>>> How to find the maximum element and min element of a col in a csv file
>>> .What will be the mapper output.
>>>
>>> --
>>> *Thanks & Regards*
>>>
>>> Unmesha Sreeveni U.B
>>> Junior Developer
>>>
>>> http://www.unmeshasreeveni.blogspot.in/
>>>
>>>
>>>
>>
>>
>> --
>> Jiayu (James) Ji,
>>
>> Cell: (312)823-7393
>>
>>
>
--
*Thanks & Regards*

Unmesha Sreeveni U.B
Junior Developer

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