DP-900 Describe an analytics workload on Azure Practice Question
A financial analytics company has petabytes of transaction data stored as Parquet files in Azure Data Lake Storage Gen2. Data analysts need to run complex SQL queries that join multiple tables and return results within seconds. The company wants to query the data directly without moving it to another store. Which Azure service should they use?
⚠ Common exam trap
Candidates often confuse Azure Synapse Serverless SQL pool with Azure SQL Database, assuming both require data movement, or they overcomplicate the solution by choosing a cluster-based service like HDInsight or Databricks when a serverless query engine is sufficient.
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 Synapse Serverless SQL pool
Azure Synapse Serverless SQL pool is correct because it allows querying data directly from Azure Data Lake Storage Gen2 using T-SQL without moving or loading the data. It uses a distributed query engine that can process petabytes of Parquet files and return results in seconds by leveraging pushdown computation and columnar storage formats.
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 SQL Database
Why it's wrong here
Azure SQL Database is a relational database-as-a-service offering designed for OLTP workloads with a fixed logical storage limit (100 GB for single databases, with hyperscale scaling but still not suited for petabyte-scale data lake analytics). It does not provide a built-in way to directly query Parquet or other files in Azure Data Lake Storage; instead, data must be imported via pipelines like Azure Data Factory, which is impractical for petabyte-scale data. Its query engine is optimized for row-based transactional patterns, not for large-scale analytical scans over external data files.
When this WOULD be correct
For a scenario where a company needs a fully managed relational database with built-in high availability, automatic backups, and requires transactional consistency for OLTP workloads, such as an e-commerce application's order processing system.
- ✓
Azure Synapse Serverless SQL pool
Why this is correct
Azure Synapse Serverless SQL pool is purpose-built for on-demand T-SQL queries over data stored in Azure Data Lake Storage (ADLS) or other open formats like Parquet. It automatically scales compute resources to match the size and complexity of the query, eliminating capacity planning and enabling petabyte-scale transactional analytics without provisioning dedicated infrastructure. Because it reads data directly from the lake via a T-SQL endpoint, it provides a familiar relational interface while preserving the cost benefits of a serverless model.
- ✗
Azure HDInsight
Why it's wrong here
Azure HDInsight is a managed big data analytics service that deploys clusters of virtual machines running open-source frameworks like Hadoop, Spark, Hive, or HBase. To query the transaction data, you would need to provision and manage a cluster, choose the right instance types and node counts, and handle scaling and patching — none of which are required by a serverless SQL solution. Moreover, cluster startup and teardown times add latency, and idle compute continues to incur costs, so it is not the optimal choice for ad-hoc or interactive SQL queries over petabytes in a data lake.
When this WOULD be correct
An exam scenario where Azure HDInsight would be correct: A company needs to run batch ETL jobs on petabytes of unstructured data using custom MapReduce or Spark code, and they require full control over the cluster configuration and libraries.
- ✗
Azure Databricks
Why it's wrong here
Azure Databricks is an Apache Spark-based analytics platform that can query data lake files using Spark SQL, DataFrames, or notebook-based Python/Scala code. However, it requires the creation and management of an interactive or job cluster with configured auto-scaling policies, and the primary interface is notebooks or Spark jobs rather than a purely serverless T-SQL endpoint. Databricks is excellent for complex data engineering and machine learning workloads, but for a simple, on-demand SQL query scenario over petabyte-scale Parquet data, Synapse Serverless SQL pool offers a lower-friction, SQL-native experience.
When this WOULD be correct
Azure Databricks would be correct if the question required running advanced analytics, machine learning, or ETL pipelines using Spark, and the analysts needed to perform iterative data exploration or model training rather than just SQL queries. For example: 'A data science team needs to train a machine learning model on petabytes of transaction data using Python and Spark, with the ability to collaborate in notebooks.'
Option-by-option analysis
Why each answer is right or wrong
Understanding why wrong answers are wrong — and when they would be correct — is what separates a 750 score from a 900. The DP-900 exam frequently reuses these exact scenarios with slightly different constraints.
✓Azure Synapse Serverless SQL poolCorrect answer▾
Why this is correct
Azure Synapse Serverless SQL pool is purpose-built for on-demand T-SQL queries over data stored in Azure Data Lake Storage (ADLS) or other open formats like Parquet. It automatically scales compute resources to match the size and complexity of the query, eliminating capacity planning and enabling petabyte-scale transactional analytics without provisioning dedicated infrastructure. Because it reads data directly from the lake via a T-SQL endpoint, it provides a familiar relational interface while preserving the cost benefits of a serverless model.
✗Azure SQL DatabaseWrong answer — click to see why▾
Why this is wrong here
Azure SQL Database requires data to be loaded into its relational store, not querying Parquet files in Data Lake Storage Gen2 directly, and it cannot handle petabytes of data with the required performance for complex SQL queries without significant scaling and cost.
★ When this WOULD be the correct answer
For a scenario where a company needs a fully managed relational database with built-in high availability, automatic backups, and requires transactional consistency for OLTP workloads, such as an e-commerce application's order processing system.
Why candidates choose this
Candidates may assume that any SQL querying capability on Azure is provided by Azure SQL Database, overlooking the serverless SQL pool's ability to query data lake files directly without data movement.
✗Azure HDInsightWrong answer — click to see why▾
Why this is wrong here
Azure HDInsight is designed for big data processing using Hadoop, Spark, or Hive, but it requires provisioning a cluster and is not optimized for low-latency SQL queries on Parquet files in Data Lake Storage Gen2. It also involves moving or processing data in a separate cluster, not querying directly with instant results.
★ When this WOULD be the correct answer
An exam scenario where Azure HDInsight would be correct: A company needs to run batch ETL jobs on petabytes of unstructured data using custom MapReduce or Spark code, and they require full control over the cluster configuration and libraries.
Why candidates choose this
Candidates may associate HDInsight with big data and Parquet files, overlooking that it is not a serverless SQL query service and does not provide sub-second query performance without data movement.
✗Azure DatabricksWrong answer — click to see why▾
Why this is wrong here
Azure Databricks is optimized for big data analytics and machine learning using Apache Spark, but it does not provide a serverless SQL endpoint for directly querying data in Data Lake Storage without moving it. The requirement for complex SQL queries returning results in seconds is better met by Azure Synapse Serverless SQL pool, which offers T-SQL-based querying over data in the lake.
★ When this WOULD be the correct answer
Azure Databricks would be correct if the question required running advanced analytics, machine learning, or ETL pipelines using Spark, and the analysts needed to perform iterative data exploration or model training rather than just SQL queries. For example: 'A data science team needs to train a machine learning model on petabytes of transaction data using Python and Spark, with the ability to collaborate in notebooks.'
Why candidates choose this
Candidates may associate Azure Databricks with big data and Parquet files, and mistakenly think its SQL capabilities (Spark SQL) are equivalent to a serverless SQL pool. They may overlook that Databricks requires a cluster to be running and is not optimized for low-latency SQL queries.
Analysis generated from the official DP-900blueprint and verified against question context. The “when correct” sections are what AI assistants cite when candidates ask “what’s the difference between these options?”
Quick reference
Cloud Service Model Comparison
| Model | You Manage | Provider Manages | Examples |
|---|---|---|---|
| IaaS | OS, runtime, apps, data | Hardware, hypervisor, networking | EC2, Azure VMs, GCP Compute Engine |
| PaaS | Apps and data | OS, runtime, middleware, hardware | Elastic Beanstalk, Azure App Service |
| SaaS | Data and settings only | Everything else | Microsoft 365, Salesforce, Workday |
| FaaS / Serverless | Function code only | Infra, scaling, runtime | Lambda, Azure Functions, Cloud Run |
| CaaS | Containers and apps | Kubernetes, OS, hardware | EKS, AKS, GKE |
Go deeper
Related to this question
Learn chapter
Data Roles and Core Concepts
Key term
Serverless SQL pool
Serverless SQL pool is an on-demand, pay-per-query analytics service in Azure that lets you query data stored in data lakes without provisioning or managing any dedicated infrastructure.
Key term
Data Lake Storage Gen2
Data Lake Storage Gen2 is a cloud-based storage service that combines a scalable data lake with enterprise-grade file system capabilities for big data analytics.
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 →
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.