AWS Certified Data Engineer Associate · Free Practice Question Medium
Question 45
A data engineer at a retail company needs to run complex queries on large datasets stored in Amazon Redshift. These queries often involve aggregating data from specific columns rather than all columns in a table. The engineer is looking for a way to optimize query performance. Which of the following Amazon Redshift features will provide the best optimization for the engineer's use case?
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A
Multi-AZ replication for faster data access
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B
Horizontal partitioning to split data across multiple nodes
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C
Row-based storage with high SSD IOPS
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D
Columnar storage for minimizing I/O operations
Reveal correct answer
Correct answer: D
A.
Multi-AZ replication improves availability but does not significantly affect query performance.
B.
While partitioning could help in distributing data, it does not directly optimize performance in querying specific columns.
C.
Row-based storage would result in more I/O because all rows, including unused columns, must be scanned.
D.
Amazon Redshift uses columnar storage for better query performance in analytical workloads. Since the engineer typically aggregates specific columns, columnar storage reduces the amount of data read from disk, minimizing I/O operations and improving query performance.
Discussion
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