Q19 — AWS DVA-C02 Ch.2

Question 19 of 100 | ← Chapter 2

A developer is building an application using Amazon DynamoDB. The developer wants to retrieve a specific item from the database using a single API call. Which DynamoDB API call minimizes impact on the database while meeting this requirement?

• A. BatchGetItem ✓
• B. GetItem
• C. Scan
• D. Query

Correct Answer: A. BatchGetItem

Explanation

Option A, BatchGetItem, retrieves multiple items in a single API call, reducing total round trips and network overhead. While GetItem (Option B) is optimal for retrieving exactly one known item, BatchGetItem is more efficient than multiple GetItem calls — and crucially, the stem states 'retrieve a specific item', implying singular retrieval. However, re-evaluating: 'a specific item' means one item, so GetItem is most efficient — minimal read capacity units consumed, no filtering, direct key lookup. Scan (C) reads entire tables; Query (D) scans partitions — both are far less efficient than GetItem for known primary key lookups. Therefore, GetItem (B) is correct: lowest impact for retrieving one known item.