HBase Mock Test


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This section presents you various set of Mock Tests related to HBase. You can download these sample mock tests at your local machine and solve offline at your convenience. Every mock test is supplied with a mock test key to let you verify the final score and grade yourself.

Questions and Answers

HBase Mock Test IV

Answer : D

Explanation

The two classes provided by co-processors to extend it custom its functionalities are −

OBSERVER AND Endpoint.

Q 2 - A coprocessor is executed when an event occurs. This type of coprocessor is known as

A - Observer

B - Listener

C - Master

D - Event handler

Answer : A

Explanation

The observer type of coprocessor is executed when an event occurs.

Q 3 - The type of coprocessors which are similar to the stored procedures in relational database is

A - Store coprocessor

B - Parallel coprocessor

C - Observer

D - Endpoint

Answer : D

Explanation

The Endpoint type of coprocessor is similar to the data abse store dprocedure in relational systems.

Q 4 - The table descriptor can be used only for which type of coprocessors?

A - Region-related

B - Master–related

C - WAL-related

D - Column Family related

Answer : A

Explanation

The table descriptors are used only for the Region servers hence the region related coprocessors.

Q 5 - The class which ised to pool client API instances to the Hbase cluster is

A - HTable()

B - HPool()

C - HBasepool()

D - HTablePool()

Answer : D

Explanation

The Htable pool is used to pool the client API instances to the Hbase cluster.

Q 6 - If one single column family exceeds the maximum file size specified by Hbase configuration then

A - Data load error is encountered

B - The column family is dropped

C - The data in the column family is truncated

D - The region is split

Answer : D

Explanation

Once the max file size is reached, the region is split into two.

Answer : A

Explanation

The Hbase tables by default are writable. They become read only by setting the readonly() option to true.

Q 8 - What is part of the directory name where Hbase data is stored?

A - Table name

B - Column qualifier

C - Column family

D - HFile

Answer : C

Explanation

The column family is part of the directory name where the Hbase data is stored. It must be made up of printable characters.

Answer : D

Explanation

The column qualifier can be left empty and still written to and read from. ALos it can not be renamed after it is created

Answer : B

Explanation

A Hbase column family cannot be renamed. The only option is to create a new column family and copy the data.

Answer : C

Explanation

in Hbase under the Hbase rot directory, each table is stored under a directory and under each table directory is a region directory for every region comprising that table.

Q 12 - The metadata of region is accessed using the file named

A - .metainfo

B - .metaregion

C - .regioninfo

D - .regionmetainfo

Answer : C

Explanation

The file .regioninfo stores the metadata information.

Answer : A

Explanation

No .tmp directory indicates no compaction happened

Answer : D

Explanation

Only the write-ahead replay cerates the recovered.edits file

Q 15 - The Hfile contains variable number of blocks. One fixed blocks in it is the block named file info block and the other one is

A - Trailer block

B - Index block

C - Data block

D - Meta blocks

Answer : A

Explanation

in an Hfile only the file infor block and trailer blocks are fixed. All others are optional.

Answer : A

Explanation

The HBAse and HDFS block sizes are not related. A HFile can spread over multiple HDFS blocks.

Q 17 - The method which can be used to access the HFiel directly without using Hbase is

A - HFile.direct()

B - HFile.access()

C - HFile.main()

D - HFile.more()

Answer : C

Explanation

The HFile.main() method has various option to read the HFile diretly without suing the HBAse like - -m option prints the meta data of the file.

Q 18 - In Hbase there are two situations when the WAL logfiles needs to be replayed. One is when the server fails. The other is when

A - The logs are full

B - Rows are deleted.

C - The cluster fails

D - Rows are updated

Answer : C

Explanation

The only two instances when the logs are replayed is when cluster starts or the server fails.

Q 19 - Before the edits in a HBAse logfile can be replayed they are separated into one logfile per region.

It is called −

A - Log splitting

B - Region splitting

C - WAL splitting

D - Replay splitting

Answer : A

Explanation

The separation of log file into one log per region is called log splitting.

Answer : D

Explanation

The Regionservers slaves are managed by the Hbase Master node

Q 21 - To see all the tables presen tin a user space in Hbase the command used is

A - Show

B - List

C - Select

D - Describe

Answer : B

Explanation

The list command displays all the tables present in the user space in Hbase

Answer : C

Explanation

Without changing the schema awe can add columns to a column family in Hbase.

Answer : B

Explanation

The table must be disabled before it is dropped.

Q 24 - The exported data using the inbuilt export utility from Hbase table is in which file format

A - Binaryfiles

B - Csv files

C - Sequence files

D - CRF files

Answer : C

Explanation

The data exported from Hbase table using the inbuilt export utility is in sequence file format.

Q 25 - In which scenario nothing is written in the WAL on HBase?

A - Record updates

B - Record Deletes

C - Bulk export

D - Bulk Load

Answer : D

Explanation

during the bulk load process nothing gets written to the WAL.

Answer Sheet

Question Number Answer Key
1 D
2 A
3 D
4 A
5 D
6 D
7 A
8 C
9 D
10 B
11 C
12 C
13 A
14 D
15 A
16 A
17 C
18 C
19 A
20 D
21 B
22 C
23 B
24 C
25 D
hbase_questions_answers.htm
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