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    <p>I code all my hadoop MR jobs in python. Let me just say that you need not use python for moving data. <strong>Use Sqoop</strong> : <a href="http://sqoop.apache.org/" rel="nofollow">http://sqoop.apache.org/</a></p> <p>Sqoop is an open-source tool that allows users to extract data from a relational database into Hadoop for further processing. And its very simple to use. All you need to do is </p> <ol> <li>Download and configure sqoop</li> <li>Create your mysql table schema</li> <li>Specify hadoop hdfs file name, result table name and column seperator.</li> </ol> <p>Read this for more info : <a href="http://archive.cloudera.com/cdh/3/sqoop/SqoopUserGuide.html" rel="nofollow">http://archive.cloudera.com/cdh/3/sqoop/SqoopUserGuide.html</a></p> <p><strong>Advantage</strong> of using sqoop is that we can now convert our hdfs data to any type of relational database (mysql,derby,hive,etc) and vice versa with a single line command</p> <p>For your use case, please do necessary changes : </p> <p>mapper.py</p> <pre><code>#!/usr/bin/env python import sys for line in sys.stdin: line = line.strip() if line.find("&lt;row") != -1 : words=line.split(' ') campaignID=words[1].split('"')[1] adGroupID=words[2].split('"')[1] print "%s:%s:"%(campaignID,adGroupID) </code></pre> <p>streaming command</p> <pre><code>bin/hadoop jar contrib/streaming/hadoop-streaming-1.0.4.jar - file /path/to/mapper.py file -mapper /path/to/mapper.py file -file /path/to/reducer.py file -reducer /path/to/reducer.py file -input /user/input -output /user/output </code></pre> <p>mysql</p> <pre><code>create database test; use test; create table testtable ( a varchar (100), b varchar(100) ); </code></pre> <p>sqoop</p> <pre><code>./sqoop export --connect jdbc:mysql://localhost/test --username root --table testnow --export-dir /user/output --input-fields-terminated-by ':' </code></pre> <p><strong>Note</strong> : </p> <ol> <li>Please change mapper as per your need </li> <li>I have used ':' as my column seperator in both the mapper and in sqoop command. Change as per needed.</li> <li>Sqoop tutorials : I have personally followed Hadoop:The Definitive Guide (Oreilly) as well as <a href="http://archive.cloudera.com/cdh/3/sqoop/SqoopUserGuide.html" rel="nofollow">http://archive.cloudera.com/cdh/3/sqoop/SqoopUserGuide.html</a>. </li> </ol>
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    1. POHow to save data from hadoop to database using python
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    1. USNicole Hu
    1. USNicole Hu
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    1. POHow to save data from hadoop to database using python
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    1. COk i have started using sqoop and trying to install it please have a look at it http://stackoverflow.com/questions/13411525/sqoop-installation-error-on-fedora-15
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    2. COActually here i want to process xml file and store data from xml file to database(in reverse actually),can u provide me a basic example on processing xml file with sqoop and saving data in to database ?
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    3. COI am assuming you were able to setup sqoop, if not I will help you with it. The hdfs output file should be sent to mysql directly using sqoop. Kindly reply whether this has helped you
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