DVA-C02 Development with AWS Services Practice Question

A developer is building a multi-region application using Amazon DynamoDB global tables. The application needs to read data from a replica table in a different region shortly after a write in the primary region. The developer notices that reads sometimes return stale data. Which of the following explains this behavior?

⚠ Common exam trap

Many candidates assume DynamoDB global tables provide immediate consistency across regions (like synchronous replication) or that they can simply switch to strong consistency reads on replicas, but the exam tests the understanding that global tables are eventually consistent and that strong consistency is not available on replica tables.

Answer choices

Why each option matters

Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.

Correct answer & explanation

✓

Global tables use asynchronous replication, introducing unavoidable replication lag.

Amazon DynamoDB global tables use asynchronous replication to propagate writes from one region to all other replica tables. This means that after a write in the primary region, there is an inherent replication lag (typically sub-second but can be higher under load or network issues) before the change is visible in other regions. The developer observes stale reads because the read is hitting a replica that has not yet received the update, which is expected behavior for eventually consistent reads on global tables.

Answer analysis

Option-by-option breakdown

For each option: why learners choose it and why it is or isn't the right answer here.

✓
Global tables use asynchronous replication, introducing unavoidable replication lag.
Why this is correct
DynamoDB Global Tables are built upon an asynchronous, multi-master replication model, which inherently leads to eventual consistency across regions. This design means there will always be an unavoidable, albeit typically brief, replication lag between regions. Data written to one region is propagated to other replica regions with a small delay, ensuring high availability and low latency writes globally but not immediate read consistency across regions.
✗
The developer must use DynamoDB Streams to capture changes and replicate them separately.
Why it's wrong here
While DynamoDB Streams are the underlying mechanism for change capture, Global Tables automatically manage the entire cross-region replication process. Developers are not required to manually configure or process DynamoDB Streams for replication when using Global Tables. Implementing custom replication via Streams would be redundant and introduce unnecessary operational complexity, as the service handles this automatically.
✗
The developer must enable strong consistency reads on the replica table.
Why it's wrong here
Strongly consistent reads in DynamoDB are only guaranteed for reads performed within the same region where the data was written or last updated. For Global Tables, reads from a replica table in a different region are always eventually consistent, reflecting the asynchronous replication model. There is no configuration option to force strong consistency for cross-region reads, as this would negate the benefits of global distribution and introduce significant latency.
✗
The global table must be configured with write forwarding.
Why it's wrong here
DynamoDB Global Tables are designed for active-active multi-region operations, allowing writes to any replica in any region. There is no specific 'write forwarding' configuration within Global Tables that dictates a primary region for all writes or directly influences cross-region read consistency. While applications might implement their own write routing logic, Global Tables themselves do not feature this concept as a managed service capability.

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DVA-C02 Development with AWS Services Practice Question

Why each option matters

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