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From Kai Voigt...@123.org>
Subject Re: Map reduce Query
Date Thu, 19 Jun 2014 10:06:31 GMT
That’s exactly what MapReduce does. The input is processed by the mapper function, and its
output will be automatically sent into the reducer function. Between mappers and reducers
we have the automatic shuffle phase which sends records with identical keys into one reducer
call.

If you want to simply not modify the data through the map phase, just don’t specify the
mapper class in your driver code. The identity function will be used for the map phase in
this case.

Kai

Am 19.06.2014 um 11:00 schrieb Shrivastava, Himnshu (GE Global Research, Non-GE) <Himnshu.Shrivastava@ge.com>:

> Can we take input in a mapper function and in some way pass it  to reducer ?
>  
> Regards,

Kai Voigt			Am Germaniahafen 1			k@123.org
					24143 Kiel					+49 160 96683050
					Germany						@KaiVoigt


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