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MapReduce >> mail # user >> Null mapper?


On 08/16/2010 05:48 PM, Ted Yu wrote:
> No.
>
> On Mon, Aug 16, 2010 at 1:25 PM, David Rosenstrauch<[EMAIL PROTECTED]>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
NEW: Monitor These Apps!
elasticsearch, apache solr, apache hbase, hadoop, redis, casssandra, amazon cloudwatch, mysql, memcached, apache kafka, apache zookeeper, apache storm, ubuntu, centOS, red hat, debian, puppet labs, java, senseiDB