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From Ted Yu <yuzhih...@gmail.com>
Subject Re: Null mapper?
Date Mon, 16 Aug 2010 22:23:33 GMT
You're right.
You need to specify a mapper.

On Mon, Aug 16, 2010 at 3:21 PM, David Rosenstrauch <darose@darose.net>wrote:

> On 08/16/2010 05:48 PM, Ted Yu wrote:
>
>> No.
>>
>> On Mon, Aug 16, 2010 at 1:25 PM, David Rosenstrauch<darose@darose.net
>> >wrote:
>>
>>  Is it possible for a M/R job to have no mapper?  i.e.:
>>> job.setMapperClass(null)?  Or is it required that one at least use an
>>> "identity mapper" (i.e., plain vanilla
>>> org.apache.hadoop.mapreduce.Mapper)?
>>>
>>> Thanks,
>>>
>>> DR
>>>
>>
> Um ...
>
> Sorry, but I'm not clear.  Which of the 2 questions were you answering "no"
> to?  :-)
>
> I'm guessing the first.?  i.e., I can't have a null mapper.  So then I need
> to supply a org.apache.hadoop.mapreduce.Mapper as a "no-op" mapper?
>
> Can you please clarify?
>
> Thanks,
>
> DR
>

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