Courseiva

DP-900 Practice Question: Describe considerations for working with non-relational data on Azure

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. Which Azure Cosmos DB API should they choose to natively support JSON documents with flexible schema?

⚠ Common exam trap

Watch out — candidates often choose the MongoDB API because they associate JSON with MongoDB, but the SQL API is the native JSON document API in Cosmos DB and is the correct answer for 'natively support JSON documents with flexible schema' in the context of Azure Cosmos DB.

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

Azure Cosmos DB SQL API

The Azure Cosmos DB SQL API (formerly DocumentDB) is the correct choice because it provides native support for storing and querying JSON documents with flexible schema, allowing each device document to have a unique DeviceID and varying attributes per device type. It offers low-latency reads by DeviceID via direct point reads using the partition key, and supports global distribution through multi-region writes and automatic replication, meeting the worldwide deployment requirement.

Answer analysis

Option-by-option breakdown

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

  • Azure Cosmos DB SQL API

    Why this is correct

    The SQL API is the native JSON document model in Azure Cosmos DB, allowing devices to be stored as schemaless JSON documents with automatic indexing and rich querying via standard SQL syntax. It provides single-digit-millisecond point reads by ID, tunable consistency, and global distribution, making it ideal for an IoT device registry.

  • Azure Cosmos DB Table API

    Why it's wrong here

    The Table API is a key-value store offering a fixed, non-relational schema that is identical to Azure Table Storage, so each device entity is a simple row with partition and row keys. It lacks the flexible JSON document structure and rich SQL query capabilities needed to model evolving device metadata effectively.

  • Azure Cosmos DB for MongoDB API

    Why it's wrong here

    The MongoDB API represents Cosmos DB's implementation of the MongoDB wire protocol, which is beneficial for migrating existing MongoDB workloads. However, it does not offer the native SQL query engine or full Cosmos DB integration, and for a greenfield IoT registry, the SQL API would be the more direct choice for JSON document storage.

  • Azure Cosmos DB Gremlin API

    Why it's wrong here

    The Gremlin API is designed for graph data modeling, where entities are nodes and relationships are edges, such as social networks or recommendation engines. An IoT device registry storing device metadata as JSON documents is not a graph problem, so this API would require an unnatural transformation of the data.

About these practice questions

This DP-900 question is part of Courseiva's 820-question bank — original exam-style content with full explanations and wrong-answer analysis, never real exam questions or exam dumps. Learn why practice questions differ from exam dumps →

How Courseiva writes practice questions · Editorial policy

JA

Written by Johnson Ajibi, MSc IT Security

Senior Network & Security Engineer · founder of Courseiva

This DP-900 practice question is part of Courseiva's free Microsoft certification practice question bank. Courseiva provides original exam-style practice questions with explanations, topic-based practice, mock exams, readiness tracking, and study analytics to help learners prepare for the DP-900 exam.