MapReduce is an algorithm for processing huge datasets on certain kinds of distributable problems using a large number of nodes
I would like to know why grouping comparator is used in secondary sort of mapreduce. According to the definitive guide …
hadoop mapreduce hadoop-partitioningI tried to run simple word count as MapReduce job. Everything works fine when run locally (all work done on …
hadoop mapreduce yarnAre setup and cleanup methods called in each mapper and reducer tasks respectively? Or are they called only once at …
hadoop mapreduceI am trying to run a map/reducer in java. Below are my files WordCount.java package counter; public class …
java hadoop mapreduceI am trying to execute the below code package test; import java.io.IOException; import java.util.*; import org.apache.…
hadoop mapreduce hive hadoop-streaming hadoop-pluginsNormally, we write the mapper in the form : public static class Map extends Mapper<**LongWritable**, Text, Text, IntWritable> …
hadoop mapreduce key-valueWe have a large dataset to analyze with multiple reduce functions. All reduce algorithm work on the same dataset generated …
hadoop mapreduceI'm working by CDH 5.1 now. It starts normal Hadoop job by YARN but hive still works with mapred. Sometimes a …
hadoop mapreduce hive yarn cloudera-cdhI have a collection of documents: date: Date users: [ { user: 1, group: 1 } { user: 5, group: 2 } ] date: Date users: [ { user: 1, group: 1 } { user: 3, group: 2 } ] …
mongodb mapreduce mongodb-query aggregation-framework