Indentify which best defines a SequenceFile?

A. A SequenceFile contains a binary encoding of an arbitrary number of homogeneous Writable objects

B. A SequenceFile contains a binary encoding of an arbitrary number of heterogeneous Writable objects

C. A SequenceFile contains a binary encoding of an arbitrary number of WritableComparable objects, in sorted order.

D. A SequenceFile contains a binary encoding of an arbitrary number key-value pairs. Each key must be the same type. Each value must be the same type.

Review the following data and Pig code.

M,38,95111

F,29,95060

F,45,95192

M,62,95102

F,56,95102

A = LOAD andapos;dataandapos; USING PigStorage(andapos;.andapos;) as (gender:Chararray, age:int,

zlp:chararray);

B = FOREACH A GENERATE age;

Which one of the following commands would save the results of B to a folder in hdfs named myoutput?

A. STORE A INTO andapos;myoutputandapos; USING PigStorage(andapos;,andapos;);

B. DUMP B using PigStorage(andapos;myoutputandapos;);

C. STORE B INTO andapos;myoutputandapos;;

D. DUMP B INTO andapos;myoutputandapos;;

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.

Can you use MapReduce to perform a relational join on two large tables sharing a key? Assume that the two tables are formatted as comma-separated files in HDFS.

A. Yes.

B. Yes, but only if one of the tables fits into memory

C. Yes, so long as both tables fit into memory.

D. No, MapReduce cannot perform relational operations.

E. No, but it can be done with either Pig or Hive.

Consider the following two relations, A and B.

A Pig JOIN statement that combined relations A by its first field and B by its second field would produce what output?

A. 2 Jim Chris 2 3 Terry 3 4 Brian 4

B. 2 cherry 2 cherry 3 orange 4 peach

C. 2 cherry Jim, Chris 3 orange Terry

4 peach Brian

D. 2 cherry Jim 2 2 cherry Chris 2 3 orange Terry 3 4 peach Brian 4