What is combiner and Partitioner in Hadoop ?
What is combiner in Hadoop and why we need it? As we know number of input splits is equal to number of mappers.Mappers will give the output of key-value pairs for all the input...
Category: Technologies
What is the importance of Record Reader and types of .XML files used in Hadoop?
Record Reader All the Mappers and Reducers will work only with Key-Value pairs. Basically we can take different formats of the file.The basic four formats of file are Text Input Format Key Value Text...
What is Reducers and Sqoop in Hadoop?
Reducers Reducers will combine all the key-value pairs output of Mappers. The data which is present between Mappers and Reducers is Intermediate data. (Key-value pairs) In Intermediate data, Values can be duplicate but not...
What is Map Reduce in Hadoop?
Some program like query languages or scripts is used to process the stored data.If client want to process the stored files, Job Tracker will apply the program on HDFS. Job tracker will send request...
HDFS Architecture and Hive in Hadoop
HDFS Architecture When client wants to store a file which has huge data using Hadoop, the following flow occurs: Initially the client will send his file to cluster where Name Node will split the...