AWS DVA-C02 Free Practice Questions — Page 3

Correct Answer: B. Store each employee's contact information in an Amazon DynamoDB table along with the object keys for the photos stored in Amazon S3.

The best architecture is to store structured contact information in DynamoDB while storing high-resolution photos in S3. DynamoDB is optimized for fast retrieval of structured data, while S3 is designed for object storage including large files like images. The DynamoDB record stores the S3 object key, allowing the application to retrieve the photo URL. Option A is problematic because DynamoDB has a 400KB item size limit, and Base64 encoding increases data size by 33%. Option C is for user authentication, not employee directories. Option D using RDS and EFS adds unnecessary complexity and cost.

Correct Answer: B. Use Amazon Cognito user pools to manage user accounts. Create an Amazon Cognito user pool authorizer in API Gateway to control access to the API. Use the Lambda function to store the photos in Amazon S3. Store the object's S3 key as part of the photo details in the DynamoDB table. Retrieve previously uploaded photos by querying DynamoDB for the S3 key.

Amazon Cognito user pools provide a fully managed user authentication service with minimal operational overhead. For photo storage, S3 is the appropriate service as DynamoDB has a 400KB item size limit and is not designed for binary data. Option A is incorrect because storing photos in DynamoDB is inefficient and may exceed item size limits. Option C creating IAM users for each application user is an anti-pattern and not scalable for tens of thousands of users. Option D requires building custom authentication logic, increasing operational overhead compared to using Cognito.

Correct Answer: C. Create an Amazon Simple Notification Service (Amazon SNS) topic. Configure the Lambda function to publish messages with specific attributes to the SNS topic. Subscribe each partner to the SNS topic. Apply the appropriate filter policy to the topic subscriptions.

Using a single SNS topic with message attributes and subscription filter policies is the most scalable approach. The Lambda function publishes all order notifications to one topic with partner-specific attributes. Each partner's subscription has a filter policy that ensures they only receive messages for their orders. Adding new partners requires only creating a new subscription with the appropriate filter policy - no code changes needed. Option A requires code changes for each new partner. Option B is not scalable and requires multiple functions. Option D sends all messages to all partners without filtering.

Correct Answer: C. Create an S3 Object Lambda access point from the S3 console. Select the removePii function. Use S3 Access Points to access the object without PII.

S3 Object Lambda allows you to add your own code to process data retrieved from S3 before returning it to an application. By creating an S3 Object Lambda access point and configuring it with the removePii Lambda function, third-party users accessing through this access point will receive documents with PII removed, while internal users can access the original through the standard access point. This maintains a single copy of the document while serving different views based on access method. S3 event notifications (Options A and B) don't work for GET operations and can't modify returned data.

Correct Answer: B. Use a function alias with different versions.

Lambda function aliases combined with versioning provide the simplest way to manage and roll back Lambda deployments. Each deployment can be published as a new version, and an alias (like 'prod' or 'live') can point to any version. Rolling back is as simple as updating the alias to point to a previous version - this is instantaneous and requires no redeployment. OpsWorks and CodePipeline add unnecessary complexity for this use case. Maintaining packages in S3 requires manual redeployment for rollbacks, increasing operational overhead.