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copied!<blockquote> <p>I have found this but it requires to use MySQL at both input and output while I need it at only output.</p> </blockquote> <p>The InputFormat (DBInputFormat) is independent of the OutputFormat (DBOutputFormat). It should be possible be possible to read from HBase in the Mapper and write to a DB in the Reducer.</p> <p>With the new MR API set the Job#setInputFormat and Job#setOutputFormat, with the old MR API set the JobConf#setInputFormat and JobConf#setOutputFormat appropriately to what input/output format is required. Both these formats need not be same. It should be possible to read from an XML in a mapper and write to a Queue in the Reducer also if required.</p> <blockquote> <p>Also, above link uses some deprecated classes from org.apache.hadoop.mapred package for which a new package org.apache.hadoop.mapreduce is available now, however I am not able to find any tutorial using this new package till now.</p> </blockquote> <p>If you are comfortable with the old API, then go ahead and use it. There is <a href="https://stackoverflow.com/questions/7598422/is-it-better-to-use-the-mapred-or-the-mapreduce-package-to-create-a-hadoop-job/7600339#7600339">not much difference</a> in the functionality between the new and the old API. There are two DBInputFormat for the old and the new API. Make sure you don't mix the old/new InputFormats with the old/new MR API.</p> <p>Here is a <a href="http://sonerbalkir.blogspot.com/2010/01/new-hadoop-api-020x.html" rel="nofollow noreferrer">tutorial</a> on the new API.</p>

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