IBM IBM Certifications C2090-101 Questions & Answers

• Question 21:

  Which ONE of the following statements regarding Sqoop is TRUE?

  A. By default, data is compressed with Sqoop

  B. Sqoop can only read committed transactions from a source database, not uncommitted ones

  C. When performing parallel imports, Sqoop always uses the primary key column in a table as the splitting column

  D. When performing parallel imports, each degree of parallelism corresponds to a concurrent database connection

  Correct Answer: B

  By default, Sqoop uses the read committed transaction isolation in the mappers to import data. This may not be the ideal in all ETL workflows and it may desired to reduce the isolation guarantees. The --relaxedisolation option can be used to instruct Sqoop to use read uncommitted isolation level.

  Reference: https://sqoop.apache.org/docs/1.4.6/SqoopUserGuide.html

• Question 22:

  Which Big SQL file format could be expected to result in a longer running query?

  A. Text

  B. Avro

  C. Parquet

  D. Sequence_text

  Correct Answer: C

  Reference: https://www.ibm.com/developerworks/data/library/techarticle/dm-1510-parquet-big-sql/ index.html

• Question 23:

  Which keyword can be inserted before a Jaql statement to understand how it may be rewritten into MapReduce?

  A. explain

  B. describe

  C. transcribe

  D. mapreduce

  Correct Answer: D

• Question 24:

  To improve Big SQL query performance one should specify the INPUTFORMAT and OUTPUTFORMAT during which of the following?

  A. SELECT statements

  B. When the file is initially stored in HDFS

  C. CREATE and ALTER table statements

  D. While the files are accessed in your program

  Correct Answer: C

  The Hadoop environment within the IBM?InfoSphere BigInsights Version 3.0 can read a large number of storage formats. This flexibility is partially because of the INPUTFORMAT and OUTPUTFORMAT classes that you can specify on the CREATE and ALTER table statements and because of the use of installed and customized SerDe classes. The file formats listed here are available either by using explicit SQL syntax, such as STORED AS PARQUETFILE, or by using installed interfaces, such as Avro.

  Reference: https://developer.ibm.com/hadoop/2014/09/19/big-sql-3-0-file-formats-usage-performance/

• Question 25:

  A Resilient Distributed Dataset with Replicated storage level does which of the following?

  A. Protects from data loss by recomputing the data

  B. Allows you to continue running the task in case of a node failure

  C. Guarantees a performance benefit

  D. Both "Protects from data loss by recomputing the data" and "Allows you to continue running the task in case of a node failure"

  Correct Answer: A

• Question 26:

  Which of the following Hadoop command flags are used to copy data to the HDFS? (Choose two.)

  A. cp

  B. put

  C. get

  D. copyToLocal

  E. copyFromLocal

  Correct Answer: DE

  Reference: https://www.ibm.com/support/knowledgecenter/SSPT3X_4.2.0/ com.ibm.swg.im.infosphere.biginsights.import.doc/doc/data_rest_shell.html

• Question 27:

  What is a standard method of monitoring sensitive data in Hadoop?

  A. Use any database monitoring tool

  B. Use HBASE GET or hadoop fs -cat commands

  C. Use STAP on each Hadoop Node

  D. All of the above

  Correct Answer: C

  Reference: https://www.ibm.com/developerworks/data/library/techarticle/dm-1210bigdatasecurity/ index.html

• Question 28:

  For which level of Apache Spark data locality is the data closest to the code that processes it?

  A. ANY

  B. NO_PREF

  C. BACK_LOCAL

  D. NODE_LOCAL

  E. PROCESS_LOCAL

  Correct Answer: E

  Reference: https://www.ibm.com/support/knowledgecenter/SSZU2E_2.4.1/performance_tuning/ application_spark_parameters.html

• Question 29:

  The input to the Reduce function is __________.

  A. Sorted by key

  B. Sorted by value

  C. Grouped by mapper

  D. Shuffled into random order

  Correct Answer: A

  Reference: https://www.ibm.com/support/knowledgecenter/SSZUMP_7.3.0/foundations_sym/ symphony_developer_objects.html

• Question 30:

  In Hive, there are a few different storage file format that can be used.

  Which format allows data to be stored as a flat file consisting of binary key-value pairs?

  A. RCFILE

  B. ORCFILE

  C. TEXTFILE

  D. SEQUENCEFILE

  Correct Answer: A

  Reference: https://nxtgen.com/hadoop-file-formats-when-and-what-to-use