AWS Certified Developer – Associate — Question 441

A company that has multiple offices uses an Amazon DynamoDB table to store employee payroll information. Item attributes consist of employee names, office identifiers, and cumulative daily hours worked The most frequently used query extracts a report of an alphabetical subset of employees for a specific office.
Which design of the DynamoDB table primary key will have the MINIMUM performance impact?

Answer options

• A. Partition key on the office identifier and sort key on the employee name
• B. Partition key on the employee name and sort key on the office identifier
• C. Partition key on the employee name
• D. Partition key on the office identifier

Correct answer: A

Explanation

Using the office identifier as the partition key groups all employees of a specific office together, while setting the employee name as the sort key automatically stores them in alphabetical order. This composite primary key structure allows the application to perform highly efficient Query operations to retrieve alphabetical subsets of employees for a single office. Other key configurations would require inefficient Scan operations or fail to support the required sorting and filtering criteria.