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From "Liu, Keyan (NSN - CN/Beijing)" <keyan....@nsn.com>
Subject How to use the reduce result in next code part
Date Mon, 11 Jun 2012 03:09:45 GMT
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? 

William Liu

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