Why we cannot do aggregation (addition) in a mapper? Why we require reducer for that?
No Answer is Posted For this Question
Be the First to Post Answer
Explain the use of .mecia class?
How can I install Cloudera VM in my system?
What is hbase in hadoop?
Why do we need a password-less ssh in fully distributed environment?
How a task is scheduled by a jobtracker?
What happens to a namenode, when job tracker is down?
Explain the hadoop-core configuration?
What is a JobTracker in Hadoop? How many instances of JobTracker run on a Hadoop Cluster?
What is Apache Hadoop? Why is Hadoop essential for every Big Data application?
What is unstructured data?
What is a Task instance in Hadoop? Where does it run?1
Can Hadoop be compared to NOSQL database like Cassandra?
Apache Hadoop (394)
MapReduce (354)
Apache Hive (345)
Apache Pig (225)
Apache Spark (991)
Apache HBase (164)
Apache Flume (95)
Apache Impala (72)
Apache Cassandra (392)
Apache Mahout (35)
Apache Sqoop (82)
Apache ZooKeeper (65)
Apache Ambari (93)
Apache HCatalog (34)
Apache HDFS Hadoop Distributed File System (214)
Apache Kafka (189)
Apache Avro (26)
Apache Presto (15)
Apache Tajo (26)
Hadoop General (407)