Question 1hardmultiple choice
Full question →hardmultiple choiceObjective-mapped
A logistics company uses Azure Synapse Analytics dedicated SQL pool to analyze billions of shipment records. The table 'Shipments' is 10 TB and hash-distributed on 'ShipmentID'. Analysts frequently run queries that filter on 'WarehouseID' and aggregate by 'Region'. These queries are slow because they cause data movement (shuffle) across distributions. Which table design change will most improve query performance for these analytical workloads?
Answer choices
Why each option matters
Good practice is not just finding the correct option. The wrong answers often show the exact trap the exam wants you to fall into.
A
Distractor review
Change distribution to replicated table
Replicated tables are suitable for smaller dimension tables that do not change frequently. The Shipments table is a large fact table (10 TB), so replicating it to all distributions would be impractical and would consume excessive storage and cause performance issues during load.
B
Distractor review
Change distribution to round-robin
Round-robin distributes data evenly but does not co-locate data for any particular column. Queries filtering on WarehouseID would still require shuffling data across distributions, leading to slow performance.
C
Distractor review
Create a columnstore index
Dedicated SQL pool already uses columnstore indexes by default. While columnstore indexes improve compression and scan performance, they do not reduce data movement caused by distribution. The root cause is the distribution key, not the index type.
D
Best answer
Change distribution to hash on 'WarehouseID'
Hash-distributing on WarehouseID places all rows for a specific warehouse on the same compute node. Queries that filter by WarehouseID become single-distribution queries, eliminating expensive data shuffles. This directly addresses the observed performance bottleneck.
Common exam trap
Common exam trap: NAT rules depend on direction and matching traffic
NAT is not only about the public address. The inside/outside interface roles and the ACL or rule that matches traffic are just as important.
Technical deep dive
How to think about this question
NAT questions usually test address translation, overload/PAT behaviour, static mappings and whether the right traffic is being translated. Read the interface direction and address terms carefully.
KKey Concepts to Remember
- Static NAT maps one inside address to one outside address.
- PAT allows many inside hosts to share one public address using ports.
- Inside local and inside global describe the private and translated addresses.
- NAT ACLs identify traffic for translation, not always security filtering.
TExam Day Tips
- Identify inside and outside interfaces first.
- Check whether the scenario needs static NAT, dynamic NAT or PAT.
- Do not confuse NAT matching ACLs with normal packet-filtering intent.
Related practice questions
Related DP-900 practice-question pages
Use these pages to review the topic behind this question. This is how one missed question becomes focused revision.
More questions from this exam
Keep practising from the same exam bank, or move into a focused topic page if this question exposed a weak area.
Question 1
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Question 2
A data engineer needs to query data stored in CSV files in Azure Data Lake Storage Gen2 using T-SQL in Azure Synapse Analytics, without loading the data into the database. Which feature should they use?
Question 3
A data engineer needs to process raw clickstream data from multiple websites that is stored in Azure Blob Storage as JSON files. The processing must run automatically every hour, transform the data into a structured format for reporting, and handle schema changes in the source data without manual intervention. Which Azure service should be used?
Question 4
A data engineer is designing a data lake architecture in Azure. They plan to first ingest raw data from various sources into a landing zone in Azure Data Lake Storage Gen2. Then they will clean, validate, and deduplicate that data in a second zone. Finally, they will create aggregated, business-ready datasets in a third zone for analysts. This layered approach is known as which architecture?
Question 5
A data engineer needs to transform large datasets stored in Azure Data Lake Storage Gen2 using Python and Apache Spark. They want a serverless compute option that automatically scales and requires no cluster management. Which Azure service should they use?
Question 6
A company collects customer feedback forms. Each form contains always-present fields like CustomerID and SubmissionDate, but also a free-text Comments field and optional fields like Rating or ProductCategory that vary between forms. How should this data be classified?
FAQ
Questions learners often ask
What does this DP-900 question test?
Static NAT maps one inside address to one outside address.
What is the correct answer to this question?
The correct answer is: Change distribution to hash on 'WarehouseID' — Hash distribution on the column used in the WHERE clause (WarehouseID) ensures that all rows for a given warehouse are placed on the same distribution. This eliminates the need to shuffle data across distributions when filtering by WarehouseID, significantly improving query performance. Columnstore indexes can also help but are already likely in a dedicated SQL pool; the primary issue here is data movement due to poor distribution key choice.
What should I do if I get this DP-900 question wrong?
Then try more questions from the same exam bank and focus on understanding why the wrong options are tempting.
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