A financial application maintains daily transaction summaries in a Cosmos DB container. The summaries are updated by a change feed trigger that processes new transactions. The team has noticed that the trigger sometimes fails due to transient errors, and when it retries, it may double-count transactions, causing incorrect summaries. They want to ensure the summaries are accurate. What should they do?

Disable retries in the trigger to avoid double-counting.

Increase the number of change feed processor instances to reduce the chance of failures.

Use the change feed estimator to monitor lag and manually fix any discrepancies.

Use idempotent update logic in the trigger, such as storing the transaction ID in the summary document to avoid double-counting.

You are using the change feed to enforce referential integrity between two containers. When a parent document is deleted, you need to delete or update related child documents. Which change feed operation would you implement?

Use a stored procedure to cascade deletes

Process the delete event and perform a compensating action on the child container

Use TTL to expire child documents

Use a pre-trigger to prevent the delete

Microsoft Certified:Azure Cosmos DB Developer Specialty

Domain 4Objective 2

Design and Implement Change Feeds for Azure Cosmos DB for NoSQL DP-420 Practice Questions (Page 3)

Part of the Optimize an Azure Cosmos DB solution domain, which makes up ~13% of our current practice bank. Microsoft does not publish an official question count, but from its 100-minute exam (~40–65 total, ~5–8 in this domain), expect 2–3 from this objective — we provide 14 practice questions to prepare you well beyond it. (estimate)

14questions here

3free pages

7concepts

Questions 11–14

11foundation · easy
When using the Azure Functions Cosmos DB trigger, which parameter in the function signature receives the batch of changed documents?
Select an answer first
12expert · hard
A financial application maintains daily transaction summaries in a Cosmos DB container. The summaries are updated by a change feed trigger that processes new transactions. The team has noticed that the trigger sometimes fails due to transient errors, and when it retries, it may double-count transactions, causing incorrect summaries. They want to ensure the summaries are accurate. What should they do?
Select an answer first
13foundation · easy
You are using the change feed processor and want to monitor how far behind the processor is in processing changes. Which component provides this information?
Select an answer first
14foundation · easy
You are using the change feed to enforce referential integrity between two containers. When a parent document is deleted, you need to delete or update related child documents. Which change feed operation would you implement?
Select an answer first

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Design and Implement Change Feeds for Azure Cosmos DB for NoSQL DP-420 Practice Questions (Page 3)

Questions 11–14

When using the Azure Functions Cosmos DB trigger, which parameter in the function signature receives the batch of changed documents?

You are using the change feed processor and want to monitor how far behind the processor is in processing changes. Which component provides this information?

You are using the change feed to enforce referential integrity between two containers. When a parent document is deleted, you need to delete or update related child documents. Which change feed operation would you implement?

Keep studying — Optimize an Azure Cosmos DB solution