Microsoft Certified: Azure Developer Associate Azure Cosmos DB Development 2 — Questions and Answers
Question 1: Which method in the Azure Cosmos DB .NET SDK v3 is used to create or replace an item if it already exists?
- CreateItemAsync
- InsertItemAsync
- UpsertItemAsync (Correct answer)
- ReplaceItemAsync
Correct answer: UpsertItemAsync
UpsertItemAsync creates the item if it does not exist or replaces it if it does, making it idempotent for create-or-update scenarios.
Question 2: In Azure Cosmos DB SQL API queries, which clause is required when querying across all partitions?
- CROSS PARTITION JOIN
- PARTITION BY
- ENABLE CROSS PARTITION QUERY (Correct answer)
- ALLOW CROSS PARTITION
Correct answer: ENABLE CROSS PARTITION QUERY
When executing a cross-partition query via the SDK, you must set EnableCrossPartitionQuery = true in QueryRequestOptions; without a partition key filter, queries fan out to all partitions.
Question 3: What is the Azure Cosmos DB change feed?
- A log of all schema changes to a container
- A sorted list of changes to items in a container that can be read by consumers (Correct answer)
- A real-time feed of pricing changes for RU/s
- A notification service for Cosmos DB quota limits
Correct answer: A sorted list of changes to items in a container that can be read by consumers
The change feed is a persistent log of changes (inserts and updates) to items in a Cosmos DB container, readable in order by partition key within each partition.
Question 4: Which of the following is a correct way to read a single item by its ID in Azure Cosmos DB .NET SDK v3?
- container.QueryItemsAsync<T>(id)
- container.ReadItemAsync<T>(id, new PartitionKey(pk)) (Correct answer)
- container.GetItemAsync<T>(id)
- container.FetchItemAsync<T>(id, pk)
Correct answer: container.ReadItemAsync<T>(id, new PartitionKey(pk))
ReadItemAsync requires both the item ID and partition key value and is the most efficient single-item read (a point read costing 1 RU).
Question 5: Which indexing policy mode in Azure Cosmos DB indexes all paths by default?
- Lazy
- None
- Custom
- Consistent (Correct answer)
Correct answer: Consistent
Consistent indexing (the default) synchronously indexes all item paths on every write, enabling immediate query consistency.
Question 6: What is the purpose of a stored procedure in Azure Cosmos DB?
- To schedule recurring maintenance tasks on a container
- To execute a batch of operations as an ACID transaction within a single partition (Correct answer)
- To replicate data between regions automatically
- To manage container throughput dynamically
Correct answer: To execute a batch of operations as an ACID transaction within a single partition
Stored procedures in Cosmos DB are JavaScript functions executed server-side and provide ACID transaction guarantees, but only within a single logical partition.
Question 7: In Azure Cosmos DB, what NuGet package is used for the modern .NET SDK v3?
- Microsoft.Azure.DocumentDB
- Microsoft.Azure.Cosmos (Correct answer)
- Azure.Data.Cosmos
- Microsoft.Azure.CosmosDB.SDK
Correct answer: Microsoft.Azure.Cosmos
The Microsoft.Azure.Cosmos NuGet package is the official v3 SDK for .NET, replacing the older Microsoft.Azure.DocumentDB package.
Microsoft Certified: Azure Developer Associate Azure Cosmos DB Development 2
Which method in the Azure Cosmos DB .NET SDK v3 is used to create or replace an item if it already exists?