Free Practice Questions for Amazon Web Services DVA-C02 Exam

Amazon Kinesis Data Firehose is a service that delivers real-time streaming data to destinations such as Amazon S3, Amazon Redshift, Amazon OpenSearch Service, and Amazon Kinesis Data Analytics. The developer can implement Kinesis Data Firehose data transformation as an AWS Lambda function. The function can remove pattern-based customer identifiers from the data and return the modified data to Kinesis Data Firehose. The developer can set an Amazon S3 bucket as the destination of the delivery stream.

Why Option D is Correct:When using a container-based AWS Lambda function, you are responsible for updating the base image for runtime patches. Rebuilding the container with the latest Node.js patch version ensures the function is updated with the required security patches. Publishing a new version of the Lambda function makes the updated image available for use.

Why Other Options are Incorrect:

Option A:The runtime update mode applies to functions using AWS-managed runtimes, not container-based runtimes.

Option B:Redeploying the same version of the Lambda function does not apply the security patch.

Option C:Rebuilding with the AWS OS base image does not guarantee that the latest Node.js patch version is included.

AWS Documentation References:

Lambda Function Container Images

Node.js Updates in AWS Lambda

DynamoDB Accelerator (DAX) provides a managed caching layer specifically optimized for DynamoDB, reducing latency for repeated read requests.

Why Option A is Correct:

Purpose-Built: DAX is designed for DynamoDB, enabling sub-millisecond response times for frequently accessed items.

Operational Efficiency: No need for additional application-level caching logic.

Why Not Other Options:

Option B: Auto Scaling increases capacity but does not address repetitive reads.

Option C: API Gateway caching helps reduce request processing time but does not optimize DynamoDB reads.

Option D: ElastiCache is a general-purpose cache, adding unnecessary complexity for DynamoDB use cases.

Requirement Summary:

Lambda function:

Retrieves an item fromDynamoDB

Updates its attributesor creates it if it does not exist

Hasprimary key

Needsminimum required IAM permissions

Analysis of Required Permissions:

Toget an itemandupdate it or create it if it doesn't exist, the Lambda function must use the **PutItem** or **UpdateItem** API, and read with **GetItem**.

✅Valid API options:

GetItem: Read the item from the table.

UpdateItem: Update existing item attributes or insert if it doesn't exist (withUpdateExpressionandConditionExpression).

When UpdateItem is used without a conditional check for existence, it cancreatea new item if it does not exist (acts like upsert).

DescribeTable: (Optional) Used if you need table metadata (not strictly required here).

Evaluate the Choices:

Option A:

DeleteItem –❌Not needed

GetItem –✅

PutItem –✅(can create/replace but not partial update)

✅Close, but PutItemoverwrites the full item, not update-in-place. Acceptable, butUpdateItemis better suited.

Option B:

UpdateItem –✅Required to modify attributes or insert new item

GetItem –✅Required to check existence or read data

DescribeTable –✅Optional, but not harmful

✅✅BEST FIT – Matches theupdate-or-createlogic.

Option C:

GetRecords –❌This is used forDynamoDB Streams, not standard GetItem

PutItem –✅

UpdateTable –❌Used to change table settings,not data manipulation

❌Incorrect usage context

Option D:

UpdateItem, GetItem, PutItem –✅all valid

But UpdateItem alone is sufficient; including PutItem might not be necessary Also, image is faded (possibly invalid), and it's redundant

UpdateItem API:https://docs.aws.amazon.com/amazondynamodb/latest/APIReference/API_UpdateItem.html

PutItem vs UpdateItem:https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/WorkingWithItems.html

IAM actions for DynamoDB:https://docs.aws.amazon.com/service-authorization/latest/reference/list_amazondynamodb.html

Amazon Cognito User Pools: A managed user directory service, simplifying user registration and login.

Social Identity Providers: Cognito supports integration with external providers (e.g., Google, Facebook), reducing development effort.

IAM Roles for Authorization: Cognito-managed IAM roles grant fine-grained access to AWS resources (like Lambda functions).

Operational Overhead: Cognito minimizes the need to manage user identities and credentials independently.

Amazon DynamoDB is a fully managed NoSQL database service that provides fast and consistent performance with seamless scalability. The developer can create a DynamoDB table and configure the table with a primary key that consists of the title as the partition key and the release year as the sort key. This will enable querying for a given title and release year efficiently. The developer can also create a global secondary index that uses the genre as the partition key and the title as the sort key. This will enable querying for a given genre efficiently. The developer can store additional properties about the cast and production crew as attributes in the DynamoDB table. These attributes can have different data types and structures, and they do not need to be consistent across items.

Reserved concurrency guarantees a specific number of concurrent executions for a critical Lambdafunction. This ensures that the critical function always has sufficient resources to execute, even if other functions are consuming concurrency.

Why Option A:

Ensures Function Availability: Reserved concurrency isolates the critical Lambda function from other functions.

Low Overhead: Configuring reserved concurrency is straightforward and requires minimal setup.

Why Not Other Options:

Option B: Provisioned concurrency is ideal for reducing cold starts, not for managing execution limits.

Option C & D: Alarms and re-invocation mechanisms add complexity without resolving the root cause.