AWS Certified Data Engineer Associate · Free Practice Question Medium
Question 62
A data engineer needs to query data from multiple sources, including an Amazon RDS PostgreSQL database and an on-premises PostgreSQL database. The engineer wants to avoid duplicating data into the Amazon Redshift cluster and minimize data transmission. Which solution should the data engineer use?
-
A
Use Amazon Athena to query the external databases and join the results with Redshift tables.
-
B
Use Redshift Spectrum to query the data directly from the external PostgreSQL databases.
-
C
Use AWS Glue to run ETL jobs that extract, transform, and load the data into Redshift tables.
-
D
Set up Redshift Federated Queries and create external schema definitions pointing to the PostgreSQL databases.
Reveal correct answer
Correct answer: D
A.
Athena is primarily used for querying data in S3, not for federated querying of relational databases.
B.
Redshift Spectrum is for querying data stored in Amazon S3, not relational databases like PostgreSQL.
C.
Using ETL jobs adds complexity and requires copying data into Redshift, which the engineer wants to avoid.
D.
Redshift Federated Queries allow querying external relational databases (like PostgreSQL) without the need for data duplication into Redshift.
Discussion
Think the marked answer is wrong, or have a better explanation? Share it below — comments appear after review.
