Question 1hardmultiple choice
Full question →hardmultiple choiceObjective-mapped
A company runs a financial application on Azure SQL Database. The Transactions table has a clustered columnstore index to support fast analytical queries on large historical datasets. However, the application also ingests a high volume of new transactions each second, and the columnstore index is causing performance degradation for these real-time inserts. The workload is hybrid (OLTP and OLAP). Which feature should the company implement to improve insert performance while still enabling efficient analytical queries on the table?
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
A: In-memory OLTP
In-memory OLTP optimizes memory-optimized tables for high-speed transactions but does not provide columnstore-based analytics on the same table in a complementary manner.
B
Distractor review
B: Elastic Query
Elastic Query enables querying across multiple Azure SQL databases; it does not address performance trade-offs within a single table.
C
Distractor review
C: Hyperscale service tier
Hyperscale is a service tier that provides fast scaling and large storage, but it does not inherently solve the conflict between columnstore inserts and rowstore inserts.
D
Best answer
D: Convert the table to a rowstore heap with a nonclustered columnstore index
A nonclustered columnstore index on a rowstore table allows efficient OLTP inserts into the rowstore while the columnstore index periodically processes batches for analytical performance, achieving a balanced hybrid workload.
Common exam trap
Common exam trap: answer the scenario, not the keyword
Many certification questions include familiar terms but test a specific constraint. Read the exact wording before choosing an answer that is generally true but wrong for this case.
Technical deep dive
How to think about this question
This question should be treated as a scenario, not a definition check. Identify the problem, the constraint and the best action. Then compare each option against those facts.
KKey Concepts to Remember
- Read the scenario before looking for a memorised answer.
- Find the constraint that changes the correct option.
- Eliminate answers that are true in general but not in this case.
- Use explanations to understand the rule behind the answer.
TExam Day Tips
- Underline the problem statement mentally.
- Watch for words such as best, first, most likely and least administrative effort.
- Review why wrong options are wrong, not only why the correct option is correct.
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.
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Question 2
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Question 3
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Question 4
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Question 5
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Question 6
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FAQ
Questions learners often ask
What does this DP-900 question test?
Read the scenario before looking for a memorised answer.
What is the correct answer to this question?
The correct answer is: D: Convert the table to a rowstore heap with a nonclustered columnstore index — A nonclustered columnstore index (NCCI) on a rowstore table (heap or clustered index) allows the table to maintain a traditional rowstore structure for efficient OLTP operations, while the NCCI periodically compresses data for analytical queries. This approach balances both workloads. In-memory OLTP (A) is for high-performance OLTP but does not directly help analytical queries on the same table and cannot be combined with columnstore easily. Elastic Query (B) is for querying remote databases. Hyperscale (C) is a service tier that scales storage and compute but does not specifically address the insert/analytics conflict. Therefore, option D is correct.
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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