Here, We see Hadoop LinkedIn Skill Assessment Answers. This assessment test consists 15-20 MCQs to demonstrate your knowledge in your selected skills. MCQs comes from different topics – Hadoop Common, Hadoop Components, Hadoop Concepts, MapReduce, Using Hadoop.
Table of Contents
Q1. Partitioner controls the partitioning of what data?
- final keys
- final values
- intermediate keys✔️
- intermediate values
Q2. SQL Windowing functions are implemented in Hive using which keywords?
- UNION DISTINCT, RANK
- OVER, RANK✔️
- OVER, EXCEPT
- UNION DISTINCT, RANK
Q3. Rather than adding a Secondary Sort to a slow Reduce job, it is Hadoop best practice to perform which optimization?
- Add a partitioned shuffle to the Map job.
- Add a partitioned shuffle to the Reduce job.✔️
- Break the Reduce job into multiple, chained Reduce jobs.
- Break the Reduce job into multiple, chained Map jobs.
Q4. Hadoop Auth enforces authentication on protected resources. Once authentication has been established, it sets what type of authenticating cookie?
- encrypted HTTP
- unsigned HTTP
- compressed HTTP
- signed HTTP✔️
Q5. MapReduce jobs can be written in which language?
- Java or Python✔️
- SQL only
- SQL or Java
- Python or SQL
Q6. To perform local aggregation of the intermediate outputs, MapReduce users can optionally specify which object?
- Reducer
- Combiner✔️
- Mapper
- Counter
Q7. To verify job status, look for the value ___
in the ___
.
- SUCCEEDED; syslog
- SUCCEEDED; stdout✔️
- DONE; syslog
- DONE; stdout
Q8. Which line of code implements a Reducer method in MapReduce 2.0?
- public void reduce(Text key, Iterator<IntWritable> values, Context context){…}✔️
- public static void reduce(Text key, IntWritable[] values, Context context){…}
- public static void reduce(Text key, Iterator<IntWritable> values, Context context){…}
- public void reduce(Text key, IntWritable[] values, Context context){…}
Q9. To get the total number of mapped input records in a map job task, you should review the value of which counter?
- FileInputFormatCounter
- FileSystemCounter
- JobCounter
- TaskCounter (NOT SURE)✔️
Q10. Hadoop Core supports which CAP capabilities?
- A, P✔️
- C, A
- C, P
- C, A, P
Q11. What are the primary phases of a Reducer?
- combine, map, and reduce
- shuffle, sort, and reduce✔️
- reduce, sort, and combine
- map, sort, and combine
Q12. To set up Hadoop workflow with synchronization of data between jobs that process tasks both on disk and in memory, use the ___
service, which is ___
.
- Oozie; open source
- Oozie; commercial software
- Zookeeper; commercial software
- Zookeeper; open source✔️
Q13. For high availability, use multiple nodes of which type?
- data
- name✔️
- memory
- worker
Q14. DataNode supports which type of drives?
- hot swappable✔️
- cold swappable
- warm swappable
- non-swappable
Q15. Which method is used to implement Spark jobs?
- on disk of all workers
- on disk of the master node
- in memory of the master node
- in memory of all workers✔️
Q16. In a MapReduce job, where does the map() function run?
- on the reducer nodes of the cluster
- on the data nodes of the cluster (NOT SURE)✔️
- on the master node of the cluster
- on every node of the cluster
Q17. To reference a master file for lookups during Mapping, what type of cache should be used?
- distributed cache✔️
- local cache
- partitioned cache
- cluster cache
Q18. Skip bad records provides an option where a certain set of bad input records can be skipped when processing what type of data?
- cache inputs
- reducer inputs
- intermediate values
- map inputs✔️
Q19. Which command imports data to Hadoop from a MySQL database?
- spark import –connect jdbc:mysql://mysql.example.com/spark –username spark –warehouse-dir user/hue/oozie/deployments/spark
- sqoop import –connect jdbc:mysql://mysql.example.com/sqoop –username sqoop –warehouse-dir user/hue/oozie/deployments/sqoop
- sqoop import –connect jdbc:mysql://mysql.example.com/sqoop –username sqoop –password sqoop –warehouse-dir user/hue/oozie/deployments/sqoop✔️
- spark import –connect jdbc:mysql://mysql.example.com/spark –username spark –password spark –warehouse-dir user/hue/oozie/deployments/spark
Q20. In what form is Reducer output presented?
- compressed (NOT SURE)✔️
- sorted
- not sorted
- encrypted
Q21. Which library should be used to unit test MapReduce code?
- JUnit
- XUnit
- MRUnit✔️
- HadoopUnit
Q22. If you started the NameNode, then which kind of user must you be?
- hadoop-user
- super-user✔️
- node-user
- admin-user
Q23. State _ between the JVMs in a MapReduce job
- can be configured to be shared
- is partially shared
- is shared
- is not shared (https://www.lynda.com/Hadoop-tutorials/Understanding-Java-virtual-machines-JVMs/191942/369545-4.html)✔️
Q24. To create a MapReduce job, what should be coded first?
- a static job() method
- a Job class and instance (NOT SURE)✔️
- a job() method
- a static Job class
Q25. To connect Hadoop to AWS S3, which client should you use?
- S3A✔️
- S3N
- S3
- the EMR S3
Q26. HBase works with which type of schema enforcement?
- schema on write
- no schema
- external schema
- schema on read✔️
Q27. HDFS file are of what type?
- read-write
- read-only
- write-only
- append-only✔️
Q28. A distributed cache file path can originate from what location?
- hdfs or top
- http
- hdfs or http✔️
- hdfs
Q29. Which library should you use to perform ETL-type MapReduce jobs?
- Hive
- Pig✔️
- Impala
- Mahout
Q30. What is the output of the Reducer?
- a relational table
- an update to the input file
- a single, combined list
- a set of <key, value> pairs✔️
Q31. To optimize a Mapper, what should you perform first?
- Override the default Partitioner.
- Skip bad records.
- Break up Mappers that do more than one task into multiple Mappers.
- Combine Mappers that do one task into large Mappers.
Q32. When implemented on a public cloud, with what does Hadoop processing interact?
- files in object storage✔️
- graph data in graph databases
- relational data in managed RDBMS systems
- JSON data in NoSQL databases
Q33. In the Hadoop system, what administrative mode is used for maintenance?
- data mode
- safe mode✔️
- single-user mode
- pseudo-distributed mode
Q34. In what format does RecordWriter write an output file?
- <key, value> pairs✔️
- keys
- values
- <value, key> pairs
Q35. To what does the Mapper map input key/value pairs?
- an average of keys for values
- a sum of keys for values
- a set of intermediate key/value pairs✔️
- a set of final key/value pairs
Q36. Which Hive query returns the first 1,000 values?
- SELECT…WHERE value = 1000
- SELECT … LIMIT 1000✔️
- SELECT TOP 1000 …
- SELECT MAX 1000…
Q37. To implement high availability, how many instances of the master node should you configure?
- one
- zero
- shared
- two or more
Q38. Hadoop 2.x and later implement which service as the resource coordinator?
- kubernetes
- JobManager
- JobTracker
- YARN✔️
Q39. In MapReduce, _ have _
- tasks; jobs
- jobs; activities
- jobs; tasks✔️
- activities; tasks
Q40. What type of software is Hadoop Common?
- database
- distributed computing framework✔️
- operating system
- productivity tool
Q41. If no reduction is desired, you should set the numbers of _ tasks to zero
- combiner
- reduce✔️
- mapper
- intermediate
Q42. MapReduce applications use which of these classes to report their statistics?
- mapper
- reducer
- combiner
- counter✔️
Q43. _ is the query language, and _ is storage for NoSQL on Hadoop
- HDFS; HQL
- HQL; HBase✔️
- HDFS; SQL
- SQL; HBase
Q44. MapReduce 1.0 _ YARN
- does not include✔️
- is the same thing as
- includes
- replaces
Q45. Which type of Hadoop node executes file system namespace operations like opening, closing, and renaming files and directories?
- ControllerNode
- DataNode
- MetadataNode
- NameNode✔️
Q46. HQL queries produce which job types?
- Impala
- MapReduce
- Spark
- Pig
Q47 Suppose you are trying to finish a Pig script that converts text in the input string to uppercase. What code is needed on line 2 below?
1 data = LOAD '/user/hue/pig/examples/data/midsummer.txt'...
2
- as (text:CHAR[]); upper_case = FOREACH data GENERATE org.apache.pig.piggybank.evaluation.string.UPPER(TEXT);
- as (text:CHARARRAY); upper_case = FOREACH data GENERATE org.apache.pig.piggybank.evaluation.string.UPPER(TEXT);✔️
- as (text:CHAR[]); upper_case = FOREACH data org.apache.pig.piggybank.evaluation.string.UPPER(TEXT);
- as (text:CHARARRAY); upper_case = FOREACH data org.apache.pig.piggybank.evaluation.string.UPPER(TEXT);
Q48. In a MapReduce job, which phase runs after the Map phase completes?
- Combiner✔️
- Reducer
- Map2
- Shuffle and Sort
Q49. Where would you configure the size of a block in a Hadoop environment?
- dfs.block.size in hdfs-site.xmls✔️
- orc.write.variable.length.blocks in hive-default.xml
- mapreduce.job.ubertask.maxbytes in mapred-site.xml
- hdfs.block.size in hdfs-site.xml
Q50. Hadoop systems are _ RDBMS systems.
- replacements for
- not used with
- substitutes for
- additions for✔️
Q51. Which object can be used to distribute jars or libraries for use in MapReduce tasks?
- distributed cache✔️
- library manager
- lookup store
- registry