Engineering Questions with Answers - Multiple Choice Questions
Hadoop MCQs
1 - Question
1. HCatalog supports reading and writing files in any format for which a ________ can be written.
a) SerDE
b) SaerDear
c) DocSear
d) All of the mentioned
View Answer
Answer: a
Explanation: By default, HCatalog supports RCFile, CSV, JSON, and SequenceFile, and ORC file formats. To use a custom format, you must provide the InputFormat, OutputFormat, and SerDe.
2 - Question
2. Point out the correct statement.
a) HCat provides connectors for MapReduce
b) Apache HCatalog provides table data access for CDH components such as Pig and MapReduce
c) HCat makes Hive metadata available to users of other Hadoop tools like Pig, MapReduce and Hive
d) All of the mentioned
View Answer
Answer: b
Explanation: Table definitions are maintained in the Hive metastore.
3 - Question
3. Hive version ___________ is the first release that includes HCatalog.
a) 0.10.0
b) 0.11.0
c) 0.12.0
d) All of the mentioned
View Answer
Answer: b
Explanation: HCatalog graduated from the Apache incubator and merged with the Hive project on March 26, 2013.
4 - Question
4. HCatalog is built on top of the Hive metastore and incorporates Hive’s is ____________
a) DDL
b) DML
c) TCL
d) DCL
View Answer
Answer: a
Explanation: HCatalog provides read and write interfaces for Pig and MapReduce and uses Hive’s command line interface for issuing data definition and metadata exploration commands.
5 - Question
5. Point out the wrong statement.
a) HCatalog is a table and storage management layer for Hadoop that enables users with different data processing tools
b) There is Hive-specific interface for HCatalog
c) Data is defined using HCatalog’s command line interface (CLI)
d) All of the mentioned
View Answer
Answer: b
Explanation: Since HCatalog uses Hive’s metastore, Hive can read data in HCatalog directly.
6 - Question
6. The HCatalog interface for Pig consists of ____________ and HCatStorer, which implement the Pig load and store interfaces respectively.
a) HCLoader
b) HCatLoader
c) HCatLoad
d) None of the mentioned
View Answer
Answer: b
Explanation: HCatLoader accepts a table to read data from; you can indicate which partitions to scan by immediately following the load statement with a partition filter statement.
7 - Question
7. _____________ accepts a table to read data from and optionally a selection predicate to indicate which partitions to scan.
a) HCatOutputFormat
b) HCatInputFormat
c) OutputFormat
d) InputFormat
View Answer
Answer: b
Explanation: The HCatalog interface for MapReduce — HCatInputFormat and HCatOutputFormat — is an implementation of Hadoop InputFormat and OutputFormat.
8 - Question
8. The HCatalog __________ supports all Hive DDL that does not require MapReduce to execute.
a) Powershell
b) CLI
c) CMD
d) All of the mentioned
View Answer
Answer: b
Explanation: Data is defined using HCatalog’s command line interface (CLI).
9 - Question
9. You can write to a single partition by specifying the partition key(s) and value(s) in the ___________ method.
a) setOutput
b) setOut
c) put
d) get
View Answer
Answer: a
Explanation: You can write to multiple partitions if the partition key(s) are columns in the data being stored.
10 - Question
10. HCatalog supports the same data types as _________
a) Pig
b) Hama
c) Hive
d) Oozie
View Answer
Answer: c
Explanation: Partitions are multi-dimensional and not hierarchical. Records are divided into columns.