Given the following Pig commands:

Which one of the following statements is true?

• A. The $1 variable represents the first column of data in 'my.log'
• B. The grouped relation is not valid
• C. The severe relation is not valid
• D. The $1 variable represents the second column of data in 'my.log'

MapReduce v2 (MRv2/YARN) is designed to address which two issues?

• A. HDFS latency.
• B. Single point of failure in the NameNode.
• C. Standardize on a single MapReduce API.
• D. Ability to run frameworks other than MapReduce, such as MPI.
• E. Resource pressure on the JobTracker.
• F. Reduce complexity of the MapReduce APIs.

Which one of the following statements describes the relationship between the ResourceManager and the ApplicationMaster?

• A. The ApplicationMaster starts a single instance of the ResourceManager
• B. The ApplicationMaster requests resources from the ResourceManager
• C. The ResourceManager monitors and restarts any failed Containers of the ApplicationMaster
• D. The ApplicationMaster starts an instance of the ResourceManager within each Container

To process input key-value pairs, your mapper needs to lead a 512 MB data file in memory. What is the best way to accomplish this?

• A. Serialize the data file, insert in it the JobConf object, and read the data into memory in the configure method of the mapper.
• B. Place the data file in the DistributedCache and read the data into memory in the map method of the mapper.
• C. Place the data file in the DistributedCache and read the data into memory in the configure method of the mapper.
• D. Place the data file in the DataCache and read the data into memory in the configure method of the mapper.

Consider the following two relations, A and B.

Which Pig statement combines A by its first field and B by its second field?

• A. C = JOIN A a1, B b2;
• B. C = JOIN A SO, B $1;
• C. C = JOIN A by al, B by b2;
• D. C = DOIN B BY a1, A by b2;