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A developer is building a serverless application that uses Amazon DynamoDB. The application needs to retrieve an item by its primary key frequently. Which DynamoDB API call should the developer use to achieve the lowest latency?

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A developer is building a serverless application that uses Amazon DynamoDB. The application needs to retrieve an item by its primary key frequently. Which DynamoDB API call should the developer use to achieve the lowest latency?

Answer choices

Why each option matters

Good practice is not just finding the correct option. The wrong answers often show the exact trap the exam wants you to fall into.

A

Distractor review

Scan

Scan reads every item in the table, which is extremely inefficient for retrieving a single item. It consumes a lot of read capacity and has high latency.

B

Distractor review

Query

Query can retrieve items by partition key, but it returns all items with that key. For a single item, it is less efficient than GetItem because it may perform additional filtering.

C

Best answer

GetItem

GetItem directly retrieves an item by its primary key. It is the most efficient operation for a single item lookup, providing the lowest latency and consuming the least read capacity.

D

Distractor review

BatchGetItem

BatchGetItem is designed for retrieving multiple items in a single request. For a single item, it adds unnecessary overhead and is no better than GetItem.

Common exam trap

Common exam trap: answer the scenario, not the keyword

Many certification questions include familiar terms but test a specific constraint. Read the exact wording before choosing an answer that is generally true but wrong for this case.

Technical deep dive

How to think about this question

This question should be treated as a scenario, not a definition check. Identify the problem, the constraint and the best action. Then compare each option against those facts.

KKey Concepts to Remember

  • Read the scenario before looking for a memorised answer.
  • Find the constraint that changes the correct option.
  • Eliminate answers that are true in general but not in this case.
  • Use explanations to understand the rule behind the answer.

TExam Day Tips

  • Underline the problem statement mentally.
  • Watch for words such as best, first, most likely and least administrative effort.
  • Review why wrong options are wrong, not only why the correct option is correct.

Related practice questions

Related DVA-C02 practice-question pages

Use these pages to review the topic behind this question. This is how one missed question becomes focused revision.

More questions from this exam

Keep practising from the same exam bank, or move into a focused topic page if this question exposed a weak area.

Question 1

A developer is building a REST API using Amazon API Gateway that will serve static content from an Amazon S3 bucket. The API should cache responses for frequently accessed objects to reduce latency. Which API Gateway feature should the developer enable?

Question 2

A developer is running a web application on multiple Amazon EC2 instances behind an Application Load Balancer (ALB). The application needs to store user session state that must be available across all instances. The session data is small and temporary but must survive individual instance failures. Which AWS service should the developer use to store this session state?

Question 3

A developer has an AWS Lambda function that processes messages from an Amazon SQS standard queue. The function is idempotent and currently has a batch size of 10. The developer wants to increase throughput and increases the batch size to 100. After the change, CloudWatch metrics show a significant increase in throttles and the queue backlog is growing. The function's reserved concurrency is set to 10. What is the most effective action to resolve the throttling and improve throughput?

Question 4

A developer is managing an application running on Amazon EC2 instances behind an Application Load Balancer. Users report that the application becomes unresponsive after several hours, and restarting the instance temporarily fixes the issue. The developer suspects a memory leak but cannot add custom instrumentation. Which AWS service can collect memory utilization metrics and help identify the memory leak with minimal configuration?

Question 5

A developer is building a serverless web application using AWS Lambda and Amazon DynamoDB. The application needs to perform complex aggregations on data stored in DynamoDB. Which AWS service should the developer use to perform these aggregations efficiently without reading all the data into Lambda?

Question 6

A developer has an Amazon S3 bucket containing private user documents. The application must generate a time-limited URL for users to download their own documents without requiring the users to have AWS credentials. Which solution should the developer use?

FAQ

Questions learners often ask

What does this DVA-C02 question test?

Read the scenario before looking for a memorised answer.

What is the correct answer to this question?

The correct answer is: GetItem — The GetItem operation is the most efficient way to retrieve a single item by its primary key because it is a direct lookup. Query is designed for retrieving multiple items with the same partition key, and Scan reads the entire table, both of which consume more read capacity and have higher latency. BatchGetItem is for multiple items but incurs overhead for a single item.

What should I do if I get this DVA-C02 question wrong?

Then try more questions from the same exam bank and focus on understanding why the wrong options are tempting.

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