Hortonworks Apache Hadoop Developer Hadoop 2.0 Certification exam for Pig and Hive Developer Online Training

Hortonworks Apache Hadoop Developer Online Training

The questions for Apache Hadoop Developer were last updated at Jul 08,2025.

Exam Code: Apache Hadoop Developer
Exam Name: Hadoop 2.0 Certification exam for Pig and Hive Developer
Certification Provider: Hortonworks
Latest update: Jul 08,2025

Question #41

Which describes how a client reads a file from HDFS?

A . The client queries the NameNode for the block location(s). The NameNode returns the block location(s) to the client. The client reads the data directory off the DataNode(s).
B . The client queries all DataNodes in parallel. The DataNode that contains the requested data responds directly to the client. The client reads the data directly off the DataNode.
C . The client contacts the NameNode for the block location(s). The NameNode then queries the DataNodes for block locations. The DataNodes respond to the NameNode, and the NameNode redirects the client to the DataNode that holds the requested data block(s). The client then reads the data directly off the DataNode.
D . The client contacts the NameNode for the block location(s). The NameNode contacts the DataNode that holds the requested data block. Data is transferred from the DataNode to the NameNode, and then from the NameNode to the client.

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Question #42

For each input key-value pair, mappers can emit:

A . As many intermediate key-value pairs as designed. There are no restrictions on the types of those key-value pairs (i.e., they can be heterogeneous).
B . As many intermediate key-value pairs as designed, but they cannot be of the same type as the input key-value pair.
C . One intermediate key-value pair, of a different type.
D . One intermediate key-value pair, but of the same type.
E . As many intermediate key-value pairs as designed, as long as all the keys have the same types and all the values have the same type.

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Question #43

You write MapReduce job to process 100 files in HDFS. Your MapReduce algorithm uses TextInputFormat: the mapper applies a regular expression over input values and emits key-values pairs with the key consisting of the matching text, and the value containing the filename and byte offset. Determine the difference between setting the number of reduces to one and settings the number of reducers to zero.

A . There is no difference in output between the two settings.
B . With zero reducers, no reducer runs and the job throws an exception. With one reducer, instances of matching patterns are stored in a single file on HDFS.
C . With zero reducers, all instances of matching patterns are gathered together in one file on HDFS. With one reducer, instances of matching patterns are stored in multiple files on HDFS.
D . With zero reducers, instances of matching patterns are stored in multiple files on HDFS. With one reducer, all instances of matching patterns are gathered together in one file on HDFS.

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Question #44

In Hadoop 2.0, which one of the following statements is true about a standby NameNode?

The Standby NameNode:

A . Communicates directly with the active NameNode to maintain the state of the active NameNode.
B . Receives the same block reports as the active NameNode.
C . Runs on the same machine and shares the memory of the active NameNode.
D . Processes all client requests and block reports from the appropriate DataNodes.

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Question #45

In the reducer, the MapReduce API provides you with an iterator over Writable values.

What does calling the next () method return?

A . It returns a reference to a different Writable object time.
B . It returns a reference to a Writable object from an object pool.
C . It returns a reference to the same Writable object each time, but populated with different data.
D . It returns a reference to a Writable object. The API leaves unspecified whether this is a reused object or a new object.
E . It returns a reference to the same Writable object if the next value is the same as the previous value, or a new Writable object otherwise.

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