Question 1hardmultiple choice
Full question →hardmultiple choiceObjective-mapped
A global gaming company stores player profiles in Azure Cosmos DB. Each profile document contains PlayerID (unique), PlayerName, Email, and a nested array of Achievements. The most common query is to look up a player by PlayerID and retrieve their achievements. The company needs strong consistency for reads and writes to ensure that when a player earns an achievement, it is immediately visible. Which partition key and consistency level should they choose?
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. Partition key: PlayerID; Consistency: Eventual
PlayerID is a good partition key for point lookups, but eventual consistency does not guarantee that a write is immediately visible to reads, which violates the requirement.
B
Best answer
B. Partition key: PlayerID; Consistency: Strong
PlayerID makes each player's document a single partition, enabling efficient lookups. Strong consistency ensures that once a write is committed, subsequent reads return the latest data.
C
Distractor review
C. Partition key: Achievements; Consistency: Strong
Achievements is an array property; using it as a partition key would create many partitions with unpredictable cardinality and cannot be used for point lookups by PlayerID.
D
Distractor review
D. Partition key: Email; Consistency: Bounded staleness
Email might be a candidate but could lead to hot partitions if many players share email domains. Bounded staleness is not the strongest consistency level and may not meet the immediate visibility requirement.
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.
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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: B. Partition key: PlayerID; Consistency: Strong — For Cosmos DB, choosing a partition key that evenly distributes data and aligns with the most common query pattern is critical. Since queries are by PlayerID, using PlayerID as the partition key ensures each player's profile is in a single logical partition, making lookups efficient and single-partition operations. Strong consistency guarantees that reads always return the most recent write. Eventual consistency would not meet the immediate visibility requirement. Using Achievements as a partition key is poor because it is an array (non-unique and high cardinality). Email could work but may cause hot spots or uneven distribution if many players use the same email domain.
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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