DP-203 Design and implement data storage Practice Question
This DP-203 practice question tests your understanding of design and implement data storage. Match the stated requirement to the specific cloud service, access model, or configuration option — many options are valid in isolation but not for this scenario. After answering, compare your reasoning against the explanation and wrong-answer breakdown below. Once you have made your selection, read the full explanation to reinforce the concept and understand why each distractor is designed to mislead on exam day.
You are using Azure Synapse Analytics serverless SQL pool to query Parquet files in Azure Data Lake Storage Gen2. The query is slow and you suspect that the file layout is not optimized. You examine the files and find that each file is 50 MB. What should you do to improve query performance?
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
Merge the small files into larger files of at least 100 MB each
Option D is correct because Azure Synapse serverless SQL pool performs best when reading files of at least 100 MB each. Small files (50 MB) cause excessive metadata operations, partition discovery, and I/O overhead, leading to slower queries. Merging them into larger files reduces the number of file open/close operations and improves parallelism efficiency.
Key principle: Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
✗
Partition the data into folders by date
Why it's wrong here
Partition pruning helps but does not solve the small file problem.
✗
Compress the files with Gzip
Why it's wrong here
Compression reduces size but does not reduce the number of files.
✗
Convert the files to CSV format to reduce overhead
Why it's wrong here
CSV is not optimized for analytics and would be slower.
✓
Merge the small files into larger files of at least 100 MB each
Why this is correct
Larger files reduce metadata overhead and improve query performance.
Related concept
Read the scenario before looking for a memorised answer.
Common exam traps
Common exam trap: answer the scenario, not the keyword
The trap here is that candidates often focus on compression or format conversion to improve performance, but the real bottleneck in serverless SQL pool with many small files is the metadata and scheduling overhead, not the data size itself.
Detailed technical explanation
How to think about this question
Azure Synapse serverless SQL pool uses a distributed query engine that splits work across compute nodes. When files are too small, the engine spends disproportionate time on file listing, metadata retrieval, and scheduling tasks rather than actual data processing. The recommended file size of 100 MB to 1 GB balances parallelism and overhead; files below this threshold cause suboptimal resource utilization, especially in serverless environments where compute is scaled dynamically.
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.
TExam Day Tips
→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.
Key takeaway
Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Real-world example
How this comes up in practice
A media company stores terabytes of video archives that are accessed once a year for audit purposes. Moving these objects to a cold storage tier (Azure Archive, S3 Glacier, or Google Nearline) costs a fraction of hot storage. Questions like this test whether you understand storage tiers, access frequency tradeoffs, and retrieval latency requirements.
Related glossary terms
Concepts from this question explained
These glossary pages explain the core terms tested in this DP-203 question in full detail.
Design and implement data storage — This question tests Design and implement data storage — Read the scenario before looking for a memorised answer..
What is the correct answer to this question?
The correct answer is: Merge the small files into larger files of at least 100 MB each — Option D is correct because Azure Synapse serverless SQL pool performs best when reading files of at least 100 MB each. Small files (50 MB) cause excessive metadata operations, partition discovery, and I/O overhead, leading to slower queries. Merging them into larger files reduces the number of file open/close operations and improves parallelism efficiency.
What should I do if I get this DP-203 question wrong?
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
What is the key concept behind this question?
Read the scenario before looking for a memorised answer.
About these practice questions
Courseiva creates original exam-style practice questions with explanations and wrong-answer analysis. It does not publish real exam questions, exam dumps, or protected exam content. Learn why practice questions differ from exam dumps →
Share a tip, memory trick, or ask about the reasoning behind this question. Do not post real exam questions, leaked content, braindumps, or copyrighted exam material. Comments are moderated and may be removed without notice.
This DP-203 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-203 exam.
Question Discussion
Share a tip, memory trick, or ask about the reasoning behind this question. Do not post real exam questions, leaked content, braindumps, or copyrighted exam material. Comments are moderated and may be removed without notice.
Sign in to join the discussion.