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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 “,“. You can change this with the “mapreduce.input.keyvaluelinerecordreader.key.value.separator” property. as in Mapper Output The mapper will go through

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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, 80, 75, 89, 90” from the Scores.data file. Hadoop MapReduce

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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

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