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From Jagat Singh <jagatsi...@gmail.com>
Subject Re: How to use the reduce result in next code part
Date Mon, 11 Jun 2012 03:24:06 GMT

Just do a quick search for chain map reduce you would get example.


Jagat Singh

Sent from Mobile , short and crisp.
On 11-Jun-2012 8:40 AM, "Liu, Keyan (NSN - CN/Beijing)" <keyan.liu@nsn.com>

> **
> Hi All,
> I am using Mapreduce to scan HBase region to get the rowkey_list that
> related with one query.
> In Map period, each mapper outputs partial rowkey_list. In reduce period,
> the reducer will collect and sort all rowkey.
> If I need to use rowkey_list result of the reduce, how can transport the
> rowkey_list outside reduce?
> I have tried to write one reduce output to HDFS “/part-r-00000”, then
> read the result in HDFS, but I found the efficiency is too low.
> How can I use the reduce result in next code part? Is there one API or
> example that can be used?
> Thanks.
> Regards,
> William Liu

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