Data Warehousing on AWS Training Performance Optimization 2

Question 1

Which type of Redshift sort key uses multiple columns and is best when queries frequently filter on those columns together?

Accepted Answer

Compound sort key

Answer

Compound sort keys order data by the first column, then second, etc., and work best when queries filter on leading columns in order.

Question 2

What is an interleaved sort key best suited for in Amazon Redshift?

Accepted Answer

Queries that filter on any subset of sort key columns with equal weight

Answer

Interleaved sort keys give equal weight to all sort key columns, making them useful when different queries filter on different subsets.

Question 3

How does Amazon Redshift Spectrum improve query performance for large datasets stored in S3?

Accepted Answer

It pushes query computation down to the Spectrum layer, parallelizing across thousands of nodes

Answer

Redshift Spectrum executes queries directly against S3 data using a massively parallel processing layer, reducing data transfer.

Question 4

What is the recommended maximum number of columns for a Redshift sort key to maintain performance?

Accepted Answer

4

Answer

Redshift recommends limiting sort keys to no more than 4 columns to avoid excessive overhead during data loading and vacuuming.

Question 5

Which Redshift feature allows you to pause and resume a cluster to save costs during idle periods while retaining data?

Accepted Answer

Cluster Pause/Resume

Answer

Cluster Pause/Resume stops compute billing while preserving all data, ideal for development or infrequent workloads.

Data Warehousing on AWS Training Practice Test