Apache-Hadoop-Developer無料問題集「Hortonworks Hadoop 2.0 Certification exam for Pig and Hive Developer」

質問 1

Examine the following Pig commands:

Which one of the following statements is true?

（A）Each MapReduce task will terminate after executing for 0.2 minutes

（B）The reducers will only output the first 20% of the data passed from the mappers

（C）A random sample of approximately 20% of the data will be output

（D）The SAMPLE command generates an "unexpected symbol" error

正解：C 解答を投票する

質問 2

Given the following Hive command:
INSERT OVERWRITE TABLE mytable SELECT * FROM myothertable;
Which one of the following statements is true?

（A）The statement is not a valid Hive command

（B）A new table named mytable is created, and the contents of myothertable are copied into mytable

（C）Any existing data in mytable will be overwritten

（D）The contents of myothertable are appended to mytable

正解：C 解答を投票する

質問 3

You are developing a MapReduce job for sales reporting. The mapper will process input keys representing the year (IntWritable) and input values representing product indentifies (Text).
Indentify what determines the data types used by the Mapper for a given job.

（A）The data types specified in HADOOP_MAP_DATATYPES environment variable

（B）The InputFormat used by the job determines the mapper's input key and value types.

（C）The key and value types specified in the JobConf.setMapInputKeyClass and JobConf.setMapInputValuesClass methods

（D）The mapper-specification.xml file submitted with the job determine the mapper's input key and value types.

正解：B 解答を投票する

解説: (JPNTest メンバーにのみ表示されます)

質問 4

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

（A）Offers real-time queries and row level updates

（B）Is a relational database

（C）Allows you to define a structure for your unstructured Big Data

（D）Useful for data analysts familiar with SQL who need to do ad-hoc queries

正解：C、D 解答を投票する

質問 5

When is the earliest point at which the reduce method of a given Reducer can be called?

（A）As soon as a mapper has emitted at least one record.

（B）Not until all mappers have finished processing all records.

（C）It depends on the InputFormat used for the job.

（D）As soon as at least one mapper has finished processing its input split.

正解：B 解答を投票する

解説: (JPNTest メンバーにのみ表示されます)

質問 6

In a MapReduce job, you want each of your input files processed by a single map task. How do you configure a MapReduce job so that a single map task processes each input file regardless of how many blocks the input file occupies?

（A）Set the number of mappers equal to the number of input files you want to process.

（B）Write a custom MapRunner that iterates over all key-value pairs in the entire file.

（C）Increase the parameter that controls minimum split size in the job configuration.

（D）Write a custom FileInputFormat and override the method isSplitable to always return false.

正解：D 解答を投票する

解説: (JPNTest メンバーにのみ表示されます)

質問 7

Consider the following two relations, A and B.