A social media application allows users to post updates and like posts. After a user clicks the like button, the like count must update immediately and be exactly the same for all users viewing the post. Which data consistency model best fits this requirement?
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.
Distractor review
Eventual consistency
Eventual consistency means data will become consistent over time, but not immediately. This is not suitable for real-time like counts where users expect instant accuracy.
Best answer
Strong consistency
Strong consistency guarantees that after a write, all reads return the most recent write. This is required for the like count to be immediately accurate for all viewers.
Distractor review
Session consistency
Session consistency ensures the user sees their own writes, but other users might not see them immediately. This does not guarantee global immediate accuracy for the like count.
Distractor review
Bounded staleness consistency
Bounded staleness allows reads to be slightly behind writes within a configurable lag. This would not meet the requirement for instantaneous accurate display.
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 4
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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: Strong consistency — Strong consistency ensures that after a write operation completes, all subsequent reads will return the updated value. This is critical for applications like social media likes where immediate accuracy is required. Eventual consistency would allow temporary discrepancies, which is not acceptable here.
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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