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1. Hadoop MapReduce Basic Tutorial

Input Data & How Hadoop reads the Data

scores.data in folder:/Users/arulk/projects

Mapper Input

The Hadoop “org.apache.hadoop.mapreduce.lib.input.KeyValueTextInputFormat” class read the input as key/value pairs. The default delimiter is tab. Our data is using “

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2. Hadoop MapReduce Basic Tutorial

This extends the Part 1 tutorial 1. Hadoop MapReduce Basic Tutorial. The key difference of this tutorial is using a “TextInputFormat” instead of “KeyValueTextInputFormat“.

TextInputFormat reads

The key as line offset number starting from 0 and the values as “Science,

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MapReduce to HBase: Read from & write to

This tutorial extends 1. HBase Tutorial Getting Started & 1. Hadoop MapReduce Basic Tutorial to read an HBase table with data from the mapper and write the max marks for each subject to another HBase table from the reducer..

Input Data Marks secured by 4 students

Step 1: Let’s store this Data in HBase database as described in tutorial 1.

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