READ Free Dumps For Cloudera- CCD-410
| Question ID 12467 | Which best describes what the map method accepts and emits?
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| Option A | It accepts a single key-value pair as input and emits a single key and list of corresponding values as output
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| Option B | It accepts a single key-value pairs as input and can emit only one key-value pair as output.
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| Option C | It accepts a list key-value pairs as input and can emit only one key-value pair as output.
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| Option D | It accepts a single key-value pairs as input and can emit any number of key-value pair as output, including zero.
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| Correct Answer | D |
Explanation Explanation: public class Mapper
extends Object Maps input key/value pairs to a set of intermediate key/value pairs. Maps are the individual tasks which transform input records into a intermediate records. The transformed intermediate records need not be of the same type as the input records. A given input pair may map to zero or many output pairs. Reference: org.apache.hadoop.mapreduce Class Mapper
| Question ID 12468 | Identify the tool best suited to import a portion of a relational database every day as files
into HDFS, and generate Java classes to interact with that imported data?
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| Option A | Oozie
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| Option B | Flume
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| Option C | Pig
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| Option D | Hue
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| Option E | Hive
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| Option F | Sqoop
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| Correct Answer | F |
Explanation Explanation: Sqoop (SQL-to-Hadoop) is a straightforward command-line tool with the following capabilities: Imports individual tables or entire databases to files in HDFS Generates Java classes to allow you to interact with your imported data Provides the ability to import from SQL databases straight into your Hive data warehouse Note: Data Movement Between Hadoop and Relational Databases Data can be moved between Hadoop and a relational database as a bulk data transfer, or relational tables can be accessed from within a MapReduce map function. Note: * Cloudera's Distribution for Hadoop provides a bulk data transfer tool (i.e., Sqoop) that imports individual tables or entire databases into HDFS files. The tool also generates Java classes that support interaction with the imported data. Sqoop supports all relational databases over JDBC, and Quest Software provides a connector (i.e., OraOop) that has been optimized for access to data residing in Oracle databases. Reference: http://log.medcl.net/item/2011/08/hadoop-and-mapreduce-big-data-analytics- gartner/ (Data Movement between hadoop and relational databases, second paragraph)