DP-900 Practice Test 22 — 15 Questions

Question 1

A healthcare organization stores medical imaging files (DICOM) that are actively used by radiologists for the first 30 days. After 30 days, the files are accessed infrequently for up to 5 years. After 5 years, they must be retained for legal compliance but are accessed very rarely. The organization wants to minimize storage costs. Which strategy should they use to manage the data lifecycle in Azure Blob Storage?

Accepted Answer

Store files in the Hot tier, move to Cool tier after 30 days, then to Archive tier after 5 years.. Option B is correct because it aligns the data lifecycle with the access patterns: Hot tier for frequent initial access, Cool tier for infrequent access after 30 days, and Archive tier for long-term compliance after 5 years. Azure Blob Storage lifecycle management policies can automate these transitions, minimizing costs by using the most cost-effective tier for each phase.

Answer

Store all files in the Hot tier and use lifecycle management to move to the Archive tier after 5 years.

Answer

Store all files in the Archive tier from the beginning to minimize cost.

Answer

Store all files in the Cool tier to balance cost and access.

Question 2

A mobile game company stores player profiles and game state in Azure Cosmos DB. Each document contains playerId, level, score, inventory (an array of items), and lastLogin. The application requires fast point reads by playerId, queries to find all players within a specific score range, and global distribution with multi-region writes for low latency worldwide. They also want to use a familiar SQL-like query language. Which Azure Cosmos DB API should they choose?

Accepted Answer

Core (SQL) API. The Core (SQL) API is the correct choice because it provides native support for SQL-like queries, enabling the required point reads by playerId and range queries on score. It also offers multi-region writes for global distribution with low latency, which aligns with the application's need for worldwide player access. The document model with arrays (inventory) is directly supported, making it ideal for storing player profiles and game state.

Answer

MongoDB API

Answer

Cassandra API

Answer

Gremlin API

Question 3

A retail company stores product catalog data as JSON documents. Each product has a different set of attributes depending on its category (e.g., electronics have 'voltage', clothing has 'size'). The application needs to query products by category and price range efficiently. Which Azure data store is most appropriate for this workload?

Accepted Answer

Azure Cosmos DB. Azure Cosmos DB is the most appropriate choice because it natively supports JSON documents with flexible schemas, enabling each product to have a different set of attributes per category. Its indexing policies can be configured to efficiently support queries filtering by category and price range, and it offers low-latency, high-throughput access ideal for retail catalog workloads.

Answer

Azure SQL Database

Answer

Azure Blob Storage

Answer

Azure Table Storage

Question 4

A logistics company tracks shipments. For each shipment, metadata (ID, weight, destination) is stored in a relational table. The route history is a sequence of events (timestamp, location, status) that is frequently appended but never updated or deleted. The application needs to quickly retrieve the latest status of a shipment and occasionally run analytical queries over the full route history. The company wants to minimize storage cost and use Azure services. Which Azure data store should they choose for the route history?

Accepted Answer

Azure Blob Storage with append blobs. Azure Blob Storage with append blobs is the correct choice because route history is write-once, read-many (WORM) data that is frequently appended but never modified or deleted. Append blobs are optimized for sequential append operations, offering low-cost storage for large volumes of event data, and they support fast retrieval of the latest status by reading the last block. This minimizes storage cost while allowing occasional analytical queries over the full history via Azure Synapse or other analytics services.

Answer

Azure Cosmos DB Core (SQL) API

Answer

Azure Table Storage

Answer

Azure SQL Database with a JSON column

Question 5

A global e-commerce company uses Azure SQL Database for its order management system. They need to ensure high availability with the ability to fail over to an Azure region in a different continent in case of a regional outage. They also want to use the secondary database for read-intensive reporting without affecting the primary's performance. Which Azure SQL Database feature should they enable?

Accepted Answer

Active geo-replication. Active geo-replication is the correct choice because it creates readable secondary replicas of an Azure SQL Database in a different Azure region (including a different continent). It supports manual failover to the secondary region during an outage, and the secondary can be used for read-only query workloads like reporting without impacting the primary database's performance.

Answer

Long-term backup retention

Answer

Automatic tuning

Answer

Connection pooling

Question 6

A multinational e-commerce company uses Azure SQL Database active geo-replication to replicate a critical inventory database to a secondary region. During a regional outage, the application automatically fails over to the secondary database. After the primary region recovers, the administrator wants to make the original primary the main database again without losing any data modifications made on the secondary during the outage. What should the administrator do?

Accepted Answer

Initiate a planned failover to switch back to the original primary.. Option C is correct because a planned failover (also known as graceful failover) in Azure SQL Database active geo-replication is designed to switch roles between the primary and secondary databases without data loss. After the original primary region recovers, initiating a planned failover synchronizes all data from the current primary (the former secondary) to the original primary, making it the new primary while preserving all modifications made during the outage. This operation ensures zero data loss because it forces a final synchronization before the role swap.

Answer

Drop the geo-replication relationship, then recreate the secondary from the current primary.

Answer

Perform a forced failover to switch back to the original primary.

Answer

Delete the secondary database and restore the original primary from a backup taken before the outage.

Question 7

A mobile gaming company stores player data in Azure Cosmos DB using the Core (SQL) API. Each document contains fields: playerId, nickname, score, level, and an inventory array of item objects (each with name and type). The company wants to query all players whose score is above 5000 and who have a specific item (e.g., a sword) in their inventory. Which query clause should they use?

Accepted Answer

B) WHERE c.score > 5000 AND ARRAY_CONTAINS(c.inventory, {name: 'sword'}, true). Option B is correct because ARRAY_CONTAINS with the third parameter set to 'true' performs a partial match, checking if any element in the inventory array has a 'name' property equal to 'sword'. This is the standard way to query for an item within an array of objects in Azure Cosmos DB's SQL API, as it correctly handles the nested structure without requiring a JOIN or subquery.

Answer

A) WHERE c.score > 5000 AND c.inventory.some(item => item.name == 'sword')

Answer

C) WHERE c.score > 5000 AND c.inventory.name == 'sword'

Answer

D) WHERE c.score > 5000 AND 'sword' IN c.inventory

Question 8

A retail company uses Azure SQL Database to store a large fact table of sales transactions with millions of rows. They run complex aggregate queries (SUM, COUNT, AVG) across many rows for monthly reports. These queries take too long. Which index type should they add to the table to improve performance?

Accepted Answer

Clustered columnstore index. Clustered columnstore indexes are optimized for large fact tables and analytical workloads because they store data in a columnar format, which significantly reduces the amount of data read from disk for aggregate queries like SUM, COUNT, and AVG. This index type also uses batch processing and compression to accelerate query performance on millions of rows, making it ideal for monthly reporting queries.

Answer

Clustered B-tree index

Answer

Nonclustered rowstore index

Answer

Nonclustered columnstore index

Question 9

A real-time leaderboard for an online game needs to store player scores and quickly retrieve the top 100 players. The data must update frequently as players achieve new scores, and the application requires sub-millisecond read and write latency. Which Azure data store is best suited for this requirement?

Accepted Answer

Azure Cache for Redis. Azure Cache for Redis is an in-memory data store that provides sub-millisecond read and write latency, making it ideal for real-time leaderboards that require frequent updates and fast retrieval of top scores. Its sorted set data structure (ZADD/ZRANGEBYSCORE) allows efficient insertion of player scores and O(log N) retrieval of the top 100 players without disk I/O overhead.

Answer

Azure Cosmos DB Core (SQL) API

Answer

Azure Table Storage

Answer

Azure Blob Storage

Question 10

A media company stores user profile images in Azure Blob Storage. Regulators require that the images cannot be deleted or overwritten for a period of 90 days after upload. Which Azure Blob Storage feature should the company enable to meet this requirement?

Accepted Answer

B: Immutable storage with a time-based retention policy. Immutable storage with a time-based retention policy (also known as WORM – Write Once, Read Many) prevents blobs from being deleted or overwritten for a specified retention interval. By setting a 90-day policy, the company ensures that user profile images remain unmodifiable and undeletable during that period, directly satisfying the regulatory requirement.

Answer

A: Soft delete

Answer

C: Access tiers (Hot, Cool, Archive)

Answer

D: Lifecycle management rules

Question 11

A global gaming company uses Azure Cosmos DB to store player scores and profiles. The application reads and writes player data from multiple regions worldwide. The company wants to ensure that when a player updates their high score in one region, any subsequent read from another region will always see the latest value, even if there is network latency between regions. Which consistency level should they choose?

Accepted Answer

Strong. Strong consistency ensures that any read operation returns the most recent write across all regions. In Azure Cosmos DB, this is achieved by synchronously replicating writes to all replicas before acknowledging the write, guaranteeing that subsequent reads in any region always see the latest value, regardless of network latency.

Answer

Bounded staleness

Answer

Session

Answer

Eventual

Question 12

A social media application stores user posts as JSON documents. Each post contains fields like post_id, author, content, and timestamp. The application needs to query posts by author and date range using SQL-like queries. Additionally, the application requires the ability to traverse follower relationships as a graph to suggest new friends. The development team wants to use a single Azure Cosmos DB account to minimize management overhead. Which combination of Azure Cosmos DB APIs should they choose?

Accepted Answer

Use the SQL API for the posts and the Gremlin API for the follower graph.. Option D is correct because Azure Cosmos DB supports multiple API models within a single account, but only one API per account. To handle both SQL-like queries on JSON documents and graph traversal queries, you need separate accounts: one using the SQL API (or MongoDB API) for the document workload and another using the Gremlin API for the graph workload. The question states 'a single Azure Cosmos DB account,' which is a constraint; however, the correct answer acknowledges that you cannot mix APIs in one account, so the only way to meet both requirements is to use two accounts—one for each API. The answer D correctly pairs the SQL API for posts and the Gremlin API for the follower graph, implying two accounts.

Answer

Use the SQL API only for both workloads.

Answer

Use the MongoDB API only for both workloads.

Answer

Use the Gremlin API only for both workloads.

Question 13

A multinational e-commerce company uses Azure SQL Database for its order processing system. They need to ensure that if an entire Azure region becomes unavailable, the database remains available with minimal data loss and automatic failover. Which feature should they implement?

Accepted Answer

Active geo-replication. Active geo-replication (Option A) is correct because it creates readable secondary replicas of an Azure SQL Database in a paired Azure region, enabling automatic failover during a regional outage. This feature provides a recovery point objective (RPO) of as low as 5 seconds and a recovery time objective (RTO) of under 1 hour, ensuring minimal data loss and high availability.

Answer

Automatic tuning

Answer

Elastic pools

Answer

Serverless compute

Question 14

A database designer is creating a relational database for a library system. Each book can have multiple authors, and each author may have written many books. To avoid data redundancy, the designer creates a separate Authors table and a BookAuthors junction table. This process of organizing data to reduce redundancy and improve integrity is called:

Accepted Answer

Normalization. Normalization is the process of organizing data in a relational database to reduce redundancy and improve data integrity by dividing large tables into smaller, related tables and defining relationships between them. In this scenario, creating separate Authors and BookAuthors junction tables eliminates the redundancy of storing author information multiple times for each book, which is a classic example of normalization (specifically achieving third normal form). This directly supports the relational database goal of minimizing duplicate data and ensuring consistency.

Answer

Denormalization

Answer

Indexing

Answer

Partitioning

Question 15

Match each Azure data consistency model to its description.