DP-900 Practice Test 44 — 15 Questions

Question 1

A media company stores user profiles in Azure Cosmos DB using the Core (SQL) API. Each profile document contains a userId (unique), name, email, and a subscriptions array containing objects with a serviceName and startDate. The application needs to efficiently retrieve a single user by userId and also run a query to find all users who have a subscription to the service 'PremiumVideo'. Which partition key design is most appropriate for this workload?

Choose an answer to begin — your selection is scored in the full session.

Accepted Answer

Partition key on userId. Partitioning on userId ensures each document is evenly distributed across physical partitions, as userId is unique and used for point reads (the most efficient operation in Cosmos DB). The query for users with a 'PremiumVideo' subscription will be a cross-partition query regardless of partition key choice, but the primary workload—retrieving a single user by userId—is optimized with this design. Partitioning on userId also avoids hot partitions and adheres to the best practice of using a high-cardinality, frequently queried field as the partition key.

Answer

Partition key on email

Answer

Partition key on serviceName (extracted from subscriptions array)

Answer

Partition key on a composite key combining userId and serviceName

Question 2

You are designing a solution to store large binary files (up to 100 GB each) that are frequently read but rarely updated. The data must be accessible via HTTPS and support concurrent reads. Which Azure data store should you use?

Accepted Answer

Azure Blob Storage. Azure Blob Storage supports large blobs (up to 190.7 TiB) and is optimized for read-heavy workloads with HTTPS access and concurrent reads. Option A is wrong because Azure Files has a maximum file size of 4 TiB and is designed for file shares, not large binary blobs. Option B is wrong because Azure Cosmos DB is for NoSQL transactional data, not large binary files. Option C is wrong because Azure NetApp Files is for high-performance file workloads, but more complex and expensive for simple blob storage.

Answer

Azure Files

Answer

Azure Cosmos DB

Answer

Azure NetApp Files

Question 3

A company uses Azure Cosmos DB for a global e-commerce application. The application needs to support multi-region writes and provide strong consistency for inventory updates. Which configuration minimizes write latency while meeting the consistency requirement?

Accepted Answer

Single-region writes with strong consistency. Multi-region writes (multi-master) with strong consistency is not supported in Azure Cosmos DB. To achieve strong consistency, you must use single-region writes. Therefore, single-region writes with strong consistency (Option C) meets the requirement while minimizing write latency by avoiding the overhead of multi-region replication. Option A (multi-master with bounded staleness) provides bounded staleness, not strong consistency. Option B (single-region writes with session consistency) provides session consistency, which is weaker. Option D (multi-master with eventual consistency) provides eventual consistency, which is the weakest level.

Answer

Multi-master with bounded staleness consistency

Answer

Single-region writes with session consistency

Answer

Multi-master with eventual consistency

Question 4

A company is designing a data analytics solution. They need to store large volumes of raw data in its native format and support schema-on-read for data science exploration. Which storage technology should they use?

Accepted Answer

Azure Data Lake Storage Gen2. Azure Data Lake Storage Gen2 (ADLS Gen2) is the correct choice because it combines a hierarchical namespace with Azure Blob Storage's scalable object storage, allowing raw data to be stored in its native format (e.g., CSV, JSON, Parquet) without transformation. It supports schema-on-read, meaning the schema is applied at query time (e.g., via Apache Spark or Azure Synapse SQL), which is ideal for data science exploration where the data structure may not be predefined.

Answer

Azure Blob Storage

Answer

Azure Cosmos DB

Answer

Azure SQL Database

Question 5

A healthcare organization stores patient medical records in a relational database with columns such as PatientID, Name, and DateOfBirth. They also store radiology images as DICOM files in Azure Blob Storage. Which statement correctly classifies these data types?

Accepted Answer

Patient records are structured, and radiology images are unstructured.. Patient records in a relational database with fixed columns like PatientID, Name, and DateOfBirth adhere to a predefined schema, making them structured data. Radiology images stored as DICOM files in Azure Blob Storage have no internal schema or tabular format and are therefore unstructured data. Option C correctly matches these classifications.

Answer

Both patient records and radiology images are structured data.

Answer

Patient records are semi-structured, and radiology images are unstructured.

Answer

Patient records are unstructured, and radiology images are semi-structured.

Question 6

A telecommunications company needs to analyze call detail records (CDRs) to detect fraud patterns and minimize revenue leakage. The data arrives as a continuous stream from network switches and must be queried within seconds of ingestion to flag suspicious activity. The analysts also need to run interactive ad-hoc queries over the last 90 days of CDR data using a Kusto query language. Which Azure service should they use as the primary data store and analytics engine?

Accepted Answer

Azure Data Explorer. Azure Data Explorer is optimized for high-velocity telemetry data like CDRs, supporting ingestion of continuous streams with sub-second query latency. Its native Kusto Query Language (KQL) enables both real-time fraud detection and interactive ad-hoc queries over large time windows (e.g., 90 days) without pre-aggregation or indexing overhead.

Answer

Azure Synapse Analytics

Answer

Azure Stream Analytics

Answer

Azure Analysis Services

Question 7

A company uses Azure SQL Database for an order management system. The Orders table has millions of rows with columns: OrderID (primary key, clustered), CustomerID, OrderDate, Status (e.g., 'Shipped', 'Pending'), TotalAmount. Queries frequently filter on OrderDate and Status, and sort results by OrderDate in descending order. They return several columns including TotalAmount. Which indexing strategy will most improve query performance?

Accepted Answer

Create a nonclustered index on (OrderDate DESC, Status) INCLUDE (CustomerID, TotalAmount). It creates a covering nonclustered index that matches the query's filter and sort order exactly. The index on (OrderDate DESC, Status) allows SQL Server to seek directly on OrderDate and Status, and the descending order avoids a sort operation for the ORDER BY OrderDate DESC clause. Including CustomerID and TotalAmount as included columns makes this a covering index, so the query can be satisfied entirely from the index without key lookups to the clustered index, which is critical for performance on a table with millions of rows.

Answer

Create a clustered index on (OrderDate, Status)

Answer

Create a nonclustered index on (Status) only

Answer

Create a columnstore index on the entire table

Question 8

You are creating an Azure SQL Database and need to connect using Microsoft Entra ID authentication. Which user type must you create in the database to represent the authenticated Microsoft Entra ID identity?

Accepted Answer

Contained database user mapped to a Microsoft Entra ID identity. To authenticate using Microsoft Entra ID in Azure SQL Database, you must create a contained database user that is mapped to a Microsoft Entra ID identity. This user does not have a login in the master database but is authenticated via Entra ID. Option A is incorrect because SQL logins use SQL Server authentication, not Entra ID. Option C is incorrect because there is no concept of an 'external user' in this context; the correct term is a contained database user mapped to an Entra ID identity. Option D is incorrect because a database user without login is typically used for SQL authentication or users without a login, not for Entra ID authentication.

Answer

SQL login with password

Answer

External user from Microsoft Entra ID

Answer

Database user without login

Question 9

Which TWO features are supported by Azure SQL Database to provide high availability?

Accepted Answer

Active geo-replication. Options C and D are correct. Active geo-replication enables creating readable secondary databases in different regions for failover, while auto-failover groups manage the failover of a group of databases with automatic initiation. Option A is incorrect because Always On availability groups are an on-premises SQL Server feature, not directly used in Azure SQL Database. Option B is incorrect because point-in-time restore is a backup feature for recovery to a specific time, not for high availability. Option E is incorrect because log shipping is an on-premises disaster recovery technique not natively supported in Azure SQL Database.

Answer

Always On availability groups

Answer

Point-in-time restore

Answer

Log shipping

Question 10

A data analyst needs to combine sales data from Azure SQL Database and inventory data from Azure Cosmos DB into a single Power BI report. Which Power BI feature should they use?

Accepted Answer

Power Query. Power Query is the correct feature because it is the data connection and transformation engine in Power BI that allows you to connect to multiple data sources—such as Azure SQL Database and Azure Cosmos DB—and combine them into a single dataset for reporting. It provides a graphical interface to merge, append, and shape data from disparate sources before loading it into the data model, which is exactly what the analyst needs to do.

Answer

Power BI Desktop

Answer

DAX formulas

Answer

Dataflows

Question 11

A company develops an IoT device registry that stores device metadata as JSON documents. Each device has a unique DeviceID, and the attributes vary per device type (e.g., sensors, actuators). The application requires low-latency reads by DeviceID and needs global distribution to support devices worldwide. The team wants to use a fully managed NoSQL database in Azure. Which API should they choose for Azure Cosmos DB?

Accepted Answer

SQL API. The SQL API (formerly DocumentDB API) is the native API for Azure Cosmos DB, providing full support for querying JSON documents with a SQL-like syntax. It offers the lowest latency reads by ID (point reads) and native global distribution, making it ideal for a device registry where each device has a unique DeviceID and variable attributes. The SQL API also supports indexing all properties automatically, which is critical for the varied device types.

Answer

MongoDB API

Answer

Cassandra API

Answer

Table API

Question 12

Your team is building a real-time dashboard for monitoring website traffic. The data source is streaming click events from Azure Event Hubs. The dashboard must update within seconds. Which Azure service should you use to process the stream?

Accepted Answer

Azure Stream Analytics. Azure Stream Analytics is designed for real-time stream processing with low-latency output, making it ideal for processing click events from Event Hubs and updating a dashboard within seconds. It provides a SQL-like query language to define transformations and can output directly to Power BI or other visualization tools for near-instantaneous dashboard updates.

Answer

Azure Synapse Pipelines

Answer

Azure Data Factory

Answer

Azure Databricks Structured Streaming

Question 13

A data analyst needs to query a large dataset stored in Azure Blob Storage using serverless SQL pool in Azure Synapse Analytics. Which data format should they use to minimize storage costs while still supporting efficient querying?

Accepted Answer

Parquet. Parquet is a columnar storage format that compresses data efficiently and supports predicate pushdown, allowing serverless SQL pool in Azure Synapse to read only the necessary columns and rows. This minimizes storage costs while maintaining high query performance, unlike row-oriented formats such as CSV or JSON.

Answer

CSV

Answer

JSON

Answer

Avro

Question 14

A company runs a SQL Server database on an Azure virtual machine. They need to offload reporting queries to a read-only copy without modifying the application. Which Azure service should they use?

Accepted Answer

Azure SQL Database with read scale-out. Azure SQL Database with read scale-out (C) is correct because it creates a read-only replica of the database that can handle reporting queries without modifying the application. The application simply adds `ApplicationIntent=ReadOnly` to the connection string, and the Azure gateway automatically routes read-only queries to the secondary replica, offloading the primary from reporting workloads.

Answer

Azure Analysis Services

Answer

Azure SQL Managed Instance

Answer

Azure Synapse Analytics dedicated SQL pool

Question 15

A company stores customer information in a SQL database with fixed columns (CustomerID, Name, Email). They also store scanned PDF contracts and product images in a file storage system. Which statement correctly describes the types of data mentioned?

Accepted Answer

The customer information is structured, and the files are unstructured.. Customer information stored in fixed columns (CustomerID, Name, Email) follows a strict schema with defined data types and relationships, making it structured data. Scanned PDF contracts and product images are binary files with no inherent schema or organization, fitting the definition of unstructured data. Option C correctly pairs these classifications.

Answer

Both the customer information and the files are structured data.

Answer

The customer information is semi-structured, and the files are unstructured.

Answer

Both the customer information and the files are unstructured.