DATABASE FUNDAMENTALS
BASICS OF BIG DATA
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Logical representation of data
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Physical representation of data
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Both the above
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None of the above
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Detailed explanation-1: -Hadoop uses a logical representation of the data stored in file blocks, known as input splits. When a MapReduce client evaluates the input splits, it figures out the beginning and end of the first whole record in a block.
Detailed explanation-2: -InputSplit represents the data to be processed by an individual Mapper . Typically, it presents a byte-oriented view on the input and is the responsibility of RecordReader of the job to process this and present a record-oriented view. See Also: InputFormat, RecordReader.
Detailed explanation-3: -An InputSplit describes a unit of work that comprises a single map task in a MapReduce program. • A Map tasks may involve reading a whole file; they often involve reading only part of a file.
Detailed explanation-4: -Hadoop HDFS split large files into small chunks known as Blocks. Block is the physical representation of data.