Online Access Free Apache-Hadoop-Developer Exam Questions

What are the TWO main components of the YARN ResourceManager process? Choose 2 answers

• A.Scheduler
• B.Job Tracker
• C.Task Tracker
• D.Applications Manager

When can a reduce class also serve as a combiner without affecting the output of a MapReduce program?

• A.When the signature of the reduce method matches the signature of the combine method.
• B.Never. Combiners and reducers must be implemented separately because they serve different purposes.
• C.Always. The point of a combiner is to serve as a mini-reducer directly after the map phase to increase performance.
• D.Always. Code can be reused in Java since it is a polymorphic object-oriented programming language.
• E.When the types of the reduce operation's input key and input value match the types of the reducer's output key and output value and when the reduce operation is both communicative and associative.

Given the following Hive command:

Which one of the following statements is true?

• A.The files in the mydata folder do not move from their current location In HDFS
• B.The files in the mydata folder are copied to a subfolder of /apps/hlve/warehouse
• C.The files in the mydata folder are copied into Hive's underlying relational database
• D.The files in the mydata folder are moved to a subfolder of /apps/hive/wa re house

Indentify which best defines a SequenceFile?

• A.A SequenceFile contains a binary encoding of an arbitrary number of homogeneous Writable objects
• B.A SequenceFile contains a binary encoding of an arbitrary number key-value pairs. Each key must be the same type. Each value must be the same type.
• C.A SequenceFile contains a binary encoding of an arbitrary number of heterogeneous Writable objects
• D.A SequenceFile contains a binary encoding of an arbitrary number of WritableComparable objects, in sorted order.

Which one of the following statements is true regarding a MapReduce job?

• A.The default Hash Partitioner sends key value pairs with the same key to the same Reducer
• B.The job's Partitioner shuffles and sorts all (key.value) pairs and sends the output to all reducers
• C.The Mapper must sort its output of (key.value) pairs in descending order based on value
• D.The reduce method is invoked once for each unique value