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copied!<p>If you just want to write your job output to MySQL, I would recommend using a different output format called <code>DBOutputFormat</code> as described <a href="http://blog.cloudera.com/blog/2009/03/database-access-with-hadoop/" rel="nofollow">here</a>:</p> <blockquote> <p>A companion class, DBOutputFormat, will allow you to write results back to a database. When setting up the job, call conf.setOutputFormat(DBOutputFormat.class); and then call DBConfiguration.configureDB() as before.</p> <p>The DBOutputFormat.setOutput() method then defines how the results will be written back to the database. Its three arguments are the JobConf object for the job, a string defining the name of the table to write to, and an array of strings defining the fields of the table to populate. e.g., DBOutputFormat.setOutput(job, "employees", "employee_id", "name");.</p> <p>The same DBWritable implementation that you created earlier will suffice to inject records back into the database. The write(PreparedStatement stmt) method will be invoked on each instance of the DBWritable that you pass to the OutputCollector from the reducer. At the end of reducing, those PreparedStatement objects will be turned into INSERT statements to run against the SQL database.</p> </blockquote> <p>Where "as before" refers to this instruction:</p> <pre><code>DBConfiguration.configureDB(conf, “com.mysql.jdbc.Driver”, “jdbc:mysql://localhost/mydatabase”); </code></pre> <p>To read from MySQL it's all the same with <code>DBInputFormat</code>.</p>

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