Hortonworks HDPCD Exam Practice Test Instant Access

Question 1

Review the following data and Pig code:

What command to define B would produce the output (M,62,95l02) when invoking the DUMP operator on B?

AB = FILTER A BY (zip = = '95102' AND gender = = M');

BB= FOREACH A BY (gender = = 'M' AND zip = = '95102');

CB = JOIN A BY (gender = = 'M' AND zip = = '95102');

DB= GROUP A BY (zip = = '95102' AND gender = = 'M');

Answer : A

Question 2

Which TWO of the following statements are true regarding Hive? Choose 2 answers

AUseful for data analysts familiar with SQL who need to do ad-hoc queries

BOffers real-time queries and row level updates

CAllows you to define a structure for your unstructured Big Data

DIs a relational database

Answer : A, C

Question 3

Examine the following Hive statements:

Assuming the statements above execute successfully, which one of the following statements is true?

AHive reformats File1 into a structure that Hive can access and moves into to/user/joe/x/

BThe file named File1 is moved to to/user/joe/x/

CThe contents of File1 are parsed as comma-delimited rows and loaded into /user/joe/x/

DThe contents of File1 are parsed as comma-delimited rows and stored in a database

Answer : B

Question 4

A client application creates an HDFS file named foo.txt with a replication factor of 3. Identify which best describes the file access rules in HDFS if the file has a single block that is stored on data nodes A, B and C?

AThe file will be marked as corrupted if data node B fails during the creation of the file.

BEach data node locks the local file to prohibit concurrent readers and writers of the file.

CEach data node stores a copy of the file in the local file system with the same name as the HDFS file.

DThe file can be accessed if at least one of the data nodes storing the file is available.

Answer : D

HDFS keeps three copies of a block on three different datanodes to protect against truedata corruption. HDFS also tries to distribute these three replicas on more than one rack to protect againstdata availabilityissues. The fact that HDFS actively monitors any failed datanode(s) and upon failure detection immediately schedules re-replication of blocks (if needed) implies that three copies of data on three different nodes is sufficient to avoid corrupted files.

Note:

HDFS is designed to reliably store very large files across machines in a large cluster. It stores each file as a sequence of blocks; all blocks in a file except the last block are the same size. The blocks of a file are replicated for fault tolerance. The block size and replication factor are configurable per file. An application can specify the number of replicas of a file. The replication factor can be specified at file creation time and can be changed later. Files in HDFS are write-once and have strictly one writer at any time. The NameNode makes all decisions regarding replication of blocks. HDFS uses rack-aware replica placement policy. In default configuration there are total 3 copies of a datablock on HDFS, 2 copies are stored on datanodes on same rack and 3rd copy on a different rack.

Question 5

You need to create a job that does frequency analysis on input dat

a. You will do this by writing a Mapper that uses TextInputFormat and splits each value (a line of text from an input file) into individual characters. For each one of these characters, you will emit the character as a key and an InputWritable as the value. As this will produce proportionally more intermediate data than input data, which two resources should you expect to be bottlenecks?

AProcessor and network I/O

BDisk I/O and network I/O

CProcessor and RAM

DProcessor and disk I/O

Answer : B

Question 6

Which one of the following statements regarding the components of YARN is FALSE?

AA Container executes a specific task as assigned by the ApplicationMaster

BThe ResourceManager is responsible for scheduling and allocating resources

CA client application submits a YARW job to the ResourceManager

DThe ResourceManager monitors and restarts any failed Containers

Answer : D

Question 7

Given the following Pig command:

logevents = LOAD 'input/my.log' AS (date:chararray, levehstring, code:int, message:string);

Which one of the following statements is true?

AThe logevents relation represents the data from the my.log file, using a comma as the parsing delimiter

BThe logevents relation represents the data from the my.log file, using a tab as the parsing delimiter

CThe first field of logevents must be a properly-formatted date string or table return an error

DThe statement is not a valid Pig command

Answer : B

Hortonworks Data Platform Certified Developer HDPCD Exam Practice Test