AWS Certified Big Data – Specialty — Question 26

An organization uses Amazon Elastic MapReduce(EMR) to process a series of extract-transform-load (ETL) steps that run in sequence. The output of each step must be fully processed in subsequent steps but will not be retained.
Which of the following techniques will meet this requirement most efficiently?

Answer options

• A. Use the EMR File System (EMRFS) to store the outputs from each step as objects in Amazon Simple Storage Service (S3).
• B. Use the s3n URI to store the data to be processed as objects in Amazon S3.
• C. Define the ETL steps as separate AWS Data Pipeline activities.
• D. Load the data to be processed into HDFS, and then write the final output to Amazon S3.

Correct answer: B

Explanation

The correct answer is B because using the s3n URI allows for efficient storage of intermediate data in Amazon S3 without retaining it, fulfilling the requirement of processing outputs sequentially. Options A and D involve unnecessary complexities of using HDFS and EMRFS, which are not needed since the data will not be retained. Option C introduces an additional layer of management with AWS Data Pipeline, which is also not required for this scenario.