READ Free Dumps For Cloudera- CCD-410
| Question ID 12527 | All keys used for intermediate output from mappers must:
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| Option A | Implement a splittable compression algorithm.
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| Option B | Be a subclass of FileInputFormat.
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| Option C | Implement WritableComparable.
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| Option D | Override isSplitable.
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| Option E | Implement a comparator for speedy sorting.
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| Correct Answer | C |
Explanation Explanation: The MapReduce framework operates exclusively on
pairs, that is, the framework views the input to the job as a set of pairs and produces a set of pairs as the output of the job, conceivably of different types. The key and value classes have to be serializable by the framework and hence need to implement the Writable interface. Additionally, the key classes have to implement the WritableComparable interface to facilitate sorting by the framework. Reference: MapReduce Tutorial
| Question ID 12528 | Given a directory of files with the following structure: line number, tab character, string:
Example:
1abialkjfjkaoasdfjksdlkjhqweroij
2kadfjhuwqounahagtnbvaswslmnbfgy
3kjfteiomndscxeqalkzhtopedkfsikj
You want to send each line as one record to your Mapper. Which InputFormat should you
use to complete the line: conf.setInputFormat (____.class) ; ?
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| Option A | SequenceFileAsTextInputFormat
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| Option B | SequenceFileInputFormat
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| Option C | KeyValueFileInputFormat
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| Option D | BDBInputFormat
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| Correct Answer | C |
Explanation Explanation: http://stackoverflow.com/questions/9721754/how-to-parse-customwritable-from-text-in- hadoop