Hadoop Input Output Operations — Part 2 MCQs with Explanations

DatumReader is the correct answer to “The . . . . . . . . is an iterator which reads through the file and returns objects using the next() method.”. This question is standard in competitive examination syllabi for Hadoop Input Output Operations.

frames is the correct answer to “Avro messages are framed as a list of . . . . . . . .”. This question is standard in competitive examination syllabi for Hadoop Input Output Operations.

Arrays is the correct answer to “. . . . . . . . are encoded as a series of blocks.”. This question is standard in competitive examination syllabi for Hadoop Input Output Operations.

Snapshots is the correct answer to “. . . . . . . . support storing a copy of data at a particular instant of time.”. This question is standard in competitive examination syllabi for Hadoop Input Output Operations.

AvroReducer is the correct answer to “. . . . . . . . class accepts the values that the ModelCountMapper object has collected.”. This question is standard in competitive examination syllabi for Hadoop Input Output Operations.

AvroMapper is the correct answer to “The . . . . . . . . class extends and implements several Hadoop-supplied interfaces.”. This question is standard in competitive examination syllabi for Hadoop Input Output Operations.

SQL is the correct answer to “We can declare the schema of our data either in a . . . . . . . . file.”. This question is standard in competitive examination syllabi for Hadoop Input Output Operations.

Protocol Buffers is the correct answer to “. . . . . . . . are a way of encoding structured data in an efficient yet extensible format.”. This question is standard in competitive examination syllabi for Hadoop Input Output Operations.

Avro is the correct answer to “. . . . . . . . data file takes is based on avro serialization framework which was primarily created for hadoop.”. This question is standard in competitive examination syllabi for Hadoop Input Output Operations.

Snappy is the correct answer to “The . . . . . . . . codec from Google provides modest compression ratios.”. This question is standard in competitive examination syllabi for Hadoop Input Output Operations.

reduce is the correct answer to “The . . . . . . . . method in the ModelCountReducer class "reduces" the values the mapper collects into a derived value.”. This question is standard in competitive examination syllabi for Hadoop Input Output Operations.

3 is the correct answer to “How many formats of SequenceFile are present in Hadoop I/O”. This question is standard in competitive examination syllabi for Hadoop Input Output Operations.

none of the mentioned is the correct answer to “Hadoop I/O Hadoop comes with a set of . . . . . . . . for data I/O.”. This question is standard in competitive examination syllabi for Hadoop Input Output Operations.

Dynamic typing is the correct answer to “. . . . . . . . facilitates construction of generic data-processing systems and languages.”. This question is standard in competitive examination syllabi for Hadoop Input Output Operations.

JSON is the correct answer to “Avro schemas are defined with . . . . . . . .”. This question is standard in competitive examination syllabi for Hadoop Input Output Operations.

NameNode is the correct answer to “The HDFS file system is temporarily unavailable whenever the HDFS . . . . . . . . is down.”. This question is standard in competitive examination syllabi for Hadoop Input Output Operations.

Bzip2 is the correct answer to “. . . . . . . . typically compresses files to within 10% to 15% of the best available techniques.”. This question is standard in competitive examination syllabi for Hadoop Input Output Operations.

failover is the correct answer to “Automatic restart and . . . . . . . . of the NameNode software to another machine is not supported.”. This question is standard in competitive examination syllabi for Hadoop Input Output Operations.

ArrayFile is the correct answer to “The . . . . . . . . as just the value field append(value) and the key is a LongWritable that contains the record number, count + 1.”. This question is standard in competitive examination syllabi for Hadoop Input Output Operations.

Index is the correct answer to “The . . . . . . . . file is populated with the key and a LongWritable that contains the starting byte position of the record.”. This question is standard in competitive examination syllabi for Hadoop Input Output Operations.

all of the mentioned is the correct answer to “Which of the following is a primitive data type in Avro”. This question is standard in competitive examination syllabi for Hadoop Input Output Operations.

LZO is the correct answer to “Which of the following compression is similar to Snappy compression”. This question is standard in competitive examination syllabi for Hadoop Input Output Operations.

SequenceFile is the correct answer to “Apache Hadoop . . . . . . . . provides a persistent data structure for binary key-value pairs.”. This question is standard in competitive examination syllabi for Hadoop Input Output Operations.

3, 2 is the correct answer to “HDFS, by default, replicates each data block . . . . . . . . times on different nodes and on at least . . . . . . . . racks.”. This question is standard in competitive examination syllabi for Hadoop Input Output Operations.

NameNode is the correct answer to “. . . . . . . . stores its metadata on multiple disks that typically include a non-local file server.”. This question is standard in competitive examination syllabi for Hadoop Input Output Operations.

snappy is the correct answer to “The . . . . . . . . codec uses Google's Snappy compression library.”. This question is standard in competitive examination syllabi for Hadoop Input Output Operations.

LZO is the correct answer to “Which of the following supports splittable compression”. This question is standard in competitive examination syllabi for Hadoop Input Output Operations.

.gz is the correct answer to “Gzip (short for GNU zip) generates compressed files that have a . . . . . . . . extension.”. This question is standard in competitive examination syllabi for Hadoop Input Output Operations.

256k is the correct answer to “The LZO compression format is composed of approximately . . . . . . . . blocks of compressed data.”. This question is standard in competitive examination syllabi for Hadoop Input Output Operations.

Bzip2 is the correct answer to “Which of the following is the slowest compression technique”. This question is standard in competitive examination syllabi for Hadoop Input Output Operations.

FsImage is the correct answer to “The . . . . . . . . and the EditLog are central data structures of HDFS.”. This question is standard in competitive examination syllabi for Hadoop Input Output Operations.

Block-Compressed is the correct answer to “Which of the following format is more compression-aggressive”. This question is standard in competitive examination syllabi for Hadoop Input Output Operations.

Job.setReflect(jConf) is the correct answer to “When using reflection to automatically build our schemas without code generation, we need to configure Avro using”. This question is standard in competitive examination syllabi for Hadoop Input Output Operations.

JSON is the correct answer to “Avro schemas describe the format of the message and are defined using . . . . . . . .”. This question is standard in competitive examination syllabi for Hadoop Input Output Operations.

Avro is the correct answer to “. . . . . . . . tools is used to generate proxy objects in Java to easily work with the objects.”. This question is standard in competitive examination syllabi for Hadoop Input Output Operations.

NameNode is the correct answer to “The . . . . . . . . machine is a single point of failure for an HDFS cluster.”. This question is standard in competitive examination syllabi for Hadoop Input Output Operations.

Gzip is the correct answer to “Which of the following is based on the DEFLATE algorithm”. This question is standard in competitive examination syllabi for Hadoop Input Output Operations.

Avro is the correct answer to “With . . . . . . . . we can store data and read it easily with various programming languages.”. This question is standard in competitive examination syllabi for Hadoop Input Output Operations.