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From Pablo Musa <pa...@psafe.com>
Subject RE: Writting to HBASE in map phase
Date Tue, 10 Jul 2012 23:06:19 GMT
Great,
Thank you very much!

Abs,
Pablo

-----Original Message-----
From: Harsh J [mailto:harsh@cloudera.com] 
Sent: terça-feira, 10 de julho de 2012 17:28
To: mapreduce-user@hadoop.apache.org
Subject: Re: Writting to HBASE in map phase

Hi Pablo,

Just set your number of reduces to zero, and your TableOutputFormat will automatically kick
in at the Map stage, i.e., just add the below to your driver before you submit the job. You
need no other changes.

job.setNumReduceTasks(0);

On Wed, Jul 11, 2012 at 1:53 AM, Pablo Musa <pablo@psafe.com> wrote:
> Hey guys,
>
> I need to update a field in an HBASE table and I want to do a mapred 
> job for that.
>
> I can do it using both map and red phase. However, it does not make 
> any sense
>
> to me, since map will pass the "Result" it is receiving to the reduce phase.
>
>
>
> I also read in the hbase mailing list someone saying that you do not 
> need the reduce,
>
> which I agree. However I do not know, and did not find any hints on 
> configuring
>
> the map phase to write into HBASE.
>
>
>
> I could use the HBASE API and write into the table, but I am not sure 
> it is a good idea.
>
>
>
> Thanks,
>
> Pablo



--
Harsh J

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