Data Base Management System Lab Reference

 Data Base Management System Lab Reference

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MapReduce Matrix Multiplication Code

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Word Count MapReduce Code

  Mapper Logic: import java.io.IOException; import java.util.StringTokenizer; import org.apache.hadoop.io.IntWritable; import org.apache.hadoop.io.LongWritable; import org.apache.hadoop.io.Text; import org.apache.hadoop.mapreduce.Mapper; public class WordCountMapper extends Mapper<LongWritable, Text, Text, IntWritable> {   @Override   public void map (LongWritable key, Text value, Context con)       throws IOException, InterruptedException {     String line = value.toString();     String[] words = line.split("\\s");     for(String s:words) {                 con.write(new Text(s), new IntWritable(1));     }   } }     Reducer Logic: import java.io.IOException; import org.apache.hadoop.io.IntWritable; import org.apache.hadoop.io.Text; import org.apache.hadoop....
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