AWS Certified Data Engineer – Associate (DEA-C01) — Question 122

A company stores employee data in Amazon Resdshift. A table names Employee uses columns named Region ID, Department ID, and Role ID as a compound sort key.

Which queries will MOST increase the speed of query by using a compound sort key of the table? (Choose two.)

Answer options

• A. Select *from Employee where Region ID=’North America’;
• B. Select *from Employee where Region ID=’North America’ and Department ID=20;
• C. Select *from Employee where Department ID=20 and Region ID=’North America’;
• D. Select *from Employee where Role ID=50;
• E. Select *from Employee where Region ID=’North America’ and Role ID=50;

Correct answer: A, B

Explanation

The correct answers, A and B, utilize the compound sort key effectively by filtering on the primary sort key, Region ID, and the secondary sort key, Department ID, respectively. Options C, D, and E do not efficiently use the compound sort key, as they either ignore the primary key or do not combine the keys optimally for performance.