Hadoop Online Quiz

Q 1 - As compared to RDBMS, Hadoop

A - Has higher data Integrity.

B - Does ACID transactions

C - IS suitable for read and write many times

D - Works better on unstructured and semi-structured data.

Q 2 - User applications can instruct the namenode to cache the files by

A - adding cache file names to cache pool

B - adding cache config to cache pool

C - adding cache directive to cache pool

D - passing the file names as parameters to the cache pool

Q 3 - The following is not permitted on HDFS files

A - Deleting

B - Renaming

C - Moving

D - Executing.

Q 4 - The hadfs command put is used to

A - Copy files from local file system to HDFS.

B - Copy files or directories from local file system to HDFS.

C - Copy files from from HDFS to local filesystem.

D - Copy files or directories from HDFS to local filesystem.

Q 5 - The output of a mapper task is

A - The Key-value pair of all the records of the dataset.

B - The Key-value pair of all the records from the input split processed by the mapper

C - Only the sorted Keys from the input split

D - The number of rows processed by the mapper task.

Q 6 - Running Start-dfs.sh results in

A - Starting namenode and datanode

B - Starting namenode only

C - Starting datanode only

D - Starting namenode and resource manager

Q 7 - The replication factor of a file in HDFS can be changed using

A - changerep

B - rerep

C - setrep

D - xrep

Q 8 - A running job in hadoop can

A - Be killed with a command

B - Can never be killed with a command

C - Can be killed only by shutting down the name node

D - Be paused and run again

Q 9 - What is distributed cache?

A - The distributed cache is special component on name node that will cache frequently used data for faster client response. It is used during reduce step.

B - The distributed cache is special component on data node that will cache frequently used data for faster client response. It is used during map step.

C - The distributed cache is a component that caches java objects.

D - The distributed cache is a component that allows developers to deploy jars for Map-Reduce processing.

Q 10 - Which one of the following statements is true regarding <key,value> pairs of a MapReduce job?

A - A key class must implement Writable.

B - A key class must implement WritableComparable.

C - A value class must implement WritableComparable.

D - A value class must extend WritableComparable.