- A
Set up connection pooling using Cloud SQL Auth Proxy and PgBouncer.
Why wrong: Connection pooling reduces connection overhead but does not identify slow queries.
- B
Create read replicas to offload read traffic.
Why wrong: Read replicas help with read scaling, not identifying slow queries.
- C
Enable the slow query log by setting the log_min_duration_statement flag.
This flag logs queries that exceed a duration threshold, helping identify slow queries.
- D
Increase the instance memory to the next tier.
Why wrong: Scaling up may help performance but does not identify the slow queries.
- E
Use EXPLAIN ANALYZE on candidate queries to see the execution plan and bottlenecks.
EXPLAIN ANALYZE shows actual execution time and plan, helping pinpoint issues.
Question 345 of 1,000
PCDE Optimising Service Performance Practice Question
This PCDE practice question tests your understanding of optimising service performance. Read the scenario carefully and evaluate each option against the stated constraints before committing to an answer. 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.
Your Cloud SQL for PostgreSQL database is experiencing slow query performance. You want to identify and optimize the slowest queries. Which TWO actions should you take? (Choose two)
Answer choices
Why each option matters
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
Enable the slow query log by setting the log_min_duration_statement flag.
To identify slow queries, enable the slow query log (via database flags) and use EXPLAIN ANALYZE to analyze query plans. Right-sizing the instance can help after identifying queries, but identifying them first requires logging and analysis. Connection pooling does not help identify slow queries.
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.
- ✗
Set up connection pooling using Cloud SQL Auth Proxy and PgBouncer.
Why it's wrong here
Connection pooling reduces connection overhead but does not identify slow queries.
- ✗
Create read replicas to offload read traffic.
Why it's wrong here
Read replicas help with read scaling, not identifying slow queries.
- ✓
Enable the slow query log by setting the log_min_duration_statement flag.
Why this is correct
This flag logs queries that exceed a duration threshold, helping identify slow queries.
Related concept
Read the scenario before looking for a memorised answer.
- ✗
Increase the instance memory to the next tier.
Why it's wrong here
Scaling up may help performance but does not identify the slow queries.
- ✓
Use EXPLAIN ANALYZE on candidate queries to see the execution plan and bottlenecks.
Why this is correct
EXPLAIN ANALYZE shows actual execution time and plan, helping pinpoint issues.
Related concept
Read the scenario before looking for a memorised answer.
Common exam traps
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.
Detailed technical explanation
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.
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.
What to study next
Got this wrong? Here's your next step.
Identify which PCDE exam domain this question belongs to, then review the specific concept being tested. Practise related questions in that domain and focus on understanding why each wrong answer is tempting — not just why the correct answer is right.
- →
Optimising Service Performance — study guide chapter
Learn the concepts, then practise the questions
- →
Optimising Service Performance practice questions
Targeted practice on this topic area only
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FAQ
Questions learners often ask
What does this PCDE question test?
Optimising Service Performance — This question tests Optimising Service Performance — Read the scenario before looking for a memorised answer..
What is the correct answer to this question?
The correct answer is: Enable the slow query log by setting the log_min_duration_statement flag. — To identify slow queries, enable the slow query log (via database flags) and use EXPLAIN ANALYZE to analyze query plans. Right-sizing the instance can help after identifying queries, but identifying them first requires logging and analysis. Connection pooling does not help identify slow queries.
What should I do if I get this PCDE question wrong?
Identify which PCDE exam domain this question belongs to, then review the specific concept being tested. Practise related questions in that domain and focus on understanding why each wrong answer is tempting — not just why the correct answer is right.
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 →
Last reviewed: Jul 4, 2026
This PCDE practice question is part of Courseiva's free Google Cloud 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 PCDE exam.
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