Engineering Questions with Answers - Multiple Choice Questions
MCQs on HCatalog with Hadoop – 1
1 - Question
__________ is a REST API for HCatalog.
a) WebHCat
b) WbHCat
c) InpHCat
d) None of the mentioned
View Answer
Answer: a
Explanation: REST stands for “representational state transfer”, a style of API based on HTTP verbs.
2 - Question
Point out the correct statement.
a) There is no guaranteed read consistency when a partition is dropped
b) Unpartitioned tables effectively have one default partition that must be created at table creation time
c) Once a partition is created, records cannot be added to it, removed from it, or updated in it
d) All of the mentioned
View Answer
Answer: d
Explanation: Partitioned tables have no partitions at create time.
3 - Question
With HCatalog _________ does not need to modify the table structure.
a) Partition
b) Columns
c) Robert
d) All of the mentioned
View Answer
Answer: c
Explanation: Without HCatalog, Robert must alter the table to add the required partition.
4 - Question
Sally in data processing uses __________ to cleanse and prepare the data.
a) Pig
b) Hive
c) HCatalog
d) Impala
View Answer
Answer: a
Explanation: Without HCatalog, Sally must be manually informed by Joe when data is available, or poll on HDFS.
5 - Question
Point out the wrong statement.
a) The original name of WebHCat was Templeton
b) Robert in client management uses Hive to analyze his clients’ results
c) With HCatalog, HCatalog cannot send a JMS message that data is available
d) All of the mentioned
View Answer
Answer: c
Explanation: The Pig job can then be restarted after analyzing client.
6 - Question
For ___________ partitioning jobs, simply specifying a custom directory is not good enough.
a) static
b) semi cluster
c) dynamic
d) all of the mentioned
View Answer
Answer: c
Explanation: Since it writes to multiple destinations, and thus, instead of a directory specification, it requires a pattern specification.
7 - Question
___________ property allows us to specify a custom dir location pattern for all the writes, and will interpolate each variable.
a) hcat.dynamic.partitioning.custom.pattern
b) hcat.append.limit
c) hcat.pig.storer.external.location
d) hcatalog.hive.client.cache.expiry.time
View Answer
Answer: a
Explanation: hcat.append.limit allows an HCatalog user to specify a custom append limit.
8 - Question
HCatalog maintains a cache of _________ to talk to the metastore.
a) HiveServer
b) HiveClients
c) HCatClients
d) All of the mentioned
View Answer
Answer: b
Explanation: HCatalog manages a cache of 1 metastore client per thread, defaulting to an expiry of 120 seconds.
9 - Question
On the write side, it is expected that the user pass in valid _________ with data correctly.
a) HRecords
b) HCatRecos
c) HCatRecords
d) None of the mentioned
View Answer
Answer: c
Explanation: In some cases where a user of HCat (such as some older versions of pig) does not support all the datatypes supported by hive, there are a few config parameters provided to handle data promotions/conversions to allow them to read data through HCatalog.
10 - Question
A float parameter, defaults to 0.0001f, which means we can deal with 1 error every __________ rows.
a) 1000
b) 10000
c) 1 million rows
d) None of the mentioned
View Answer
Answer: b
Explanation: hcat.input.bad.record.threshold property is throw out error on encountering bad record.