DP-900 Practice Question: Describe considerations for working with non-relational data on Azure
This DP-900 practice question tests your understanding of describe considerations for working with non-relational data on azure. 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.
A mobile game stores player achievements in Azure Cosmos DB. Each player has a PlayerID, and achievements are stored as JSON documents with varying fields. The most common query retrieves all achievements for a specific player. To ensure low latency and efficient throughput, which property should be chosen as the partition key?
PlayerID is the most common query filter, has high cardinality, and evenly distributes data across partitions, resulting in efficient queries and throughput.
B
Timestamp
Why wrong: Timestamp may cause hot partitions if many players achieve something at the same time, and it is not the primary query filter.
C
AchievementType
Why wrong: AchievementType has low cardinality and would concentrate data for popular achievements on a few partitions, causing hot partitions.
D
Region
Why wrong: Region may be used for geo-distribution but is not the primary query filter and could lead to uneven data distribution if players are concentrated in certain regions.
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
PlayerID
PlayerID is the correct partition key because the most common query retrieves all achievements for a specific player, and partitioning on PlayerID ensures that all documents for a given player are stored in the same physical partition. This allows the query to target a single partition, minimizing cross-partition queries and providing low latency and efficient throughput.
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.
✓
PlayerID
Why this is correct
PlayerID is the most common query filter, has high cardinality, and evenly distributes data across partitions, resulting in efficient queries and throughput.
Related concept
Read the scenario before looking for a memorised answer.
✗
Timestamp
Why it's wrong here
Timestamp may cause hot partitions if many players achieve something at the same time, and it is not the primary query filter.
✗
AchievementType
Why it's wrong here
AchievementType has low cardinality and would concentrate data for popular achievements on a few partitions, causing hot partitions.
✗
Region
Why it's wrong here
Region may be used for geo-distribution but is not the primary query filter and could lead to uneven data distribution if players are concentrated in certain regions.
Common exam traps
Common exam trap: answer the scenario, not the keyword
The trap here is that candidates often choose a high-cardinality key like Timestamp without considering the query pattern, mistakenly thinking any unique value is good, but the partition key must align with the most frequent query filter to avoid cross-partition overhead.
Detailed technical explanation
How to think about this question
Under the hood, Azure Cosmos DB uses a hash-based partition strategy where the partition key value is hashed to determine the physical partition. Choosing a high-cardinality partition key like PlayerID ensures even data distribution and avoids hot partitions. In a real-world scenario, if PlayerID is used, a single point query (e.g., SELECT * FROM c WHERE c.PlayerID = '123') hits exactly one partition, achieving single-digit millisecond latency even at high throughput.
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 cloud solutions architect for a retail company is evaluating services for a new workload. The correct answer here reflects best practice for the specific scenario described — not a general cloud recommendation. Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option. Cloud exam questions reward reading the constraint carefully: the same technology can be right or wrong depending on the use case.
Related glossary terms
Concepts from this question explained
These glossary pages explain the core terms tested in this DP-900 question in full detail.
Describe considerations for working with non-relational data on Azure — This question tests Describe considerations for working with non-relational data on Azure — Read the scenario before looking for a memorised answer..
What is the correct answer to this question?
The correct answer is: PlayerID — PlayerID is the correct partition key because the most common query retrieves all achievements for a specific player, and partitioning on PlayerID ensures that all documents for a given player are stored in the same physical partition. This allows the query to target a single partition, minimizing cross-partition queries and providing low latency and efficient throughput.
What should I do if I get this DP-900 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-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.
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.