Courseiva
← DBS-C01
Full test
Question 878 of 1,730
Workload-Specific Database Design →hardMultiple ChoiceObjective-mapped

DBS-C01 Workload-Specific Database Design Practice Question

This DBS-C01 practice question tests your understanding of workload-specific database design. The scenario asks you to isolate a root cause — eliminate options that address a different problem before choosing. 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 company runs an e-commerce platform on Amazon RDS for MySQL with a Multi-AZ deployment. The database has a table 'orders' with 50 million rows. During Black Friday sales, the application experiences severe slowdowns. Analysis shows that the CPU utilization is at 90% and there are many slow queries that perform full table scans on the 'orders' table. The development team has already added indexes on the most queried columns, but the problem persists. The database specialist suspects that the issue is not solely due to missing indexes. They notice that the queries often filter on a combination of 'order_date', 'customer_id', and 'status', and that the data distribution is heavily skewed: 80% of orders are 'completed' status. The 'order_date' range is typically the last 30 days. What should the database specialist do to improve query performance?

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

✓

Partition the 'orders' table by 'status' and 'order_date' and create covering indexes on common query patterns.

Option A is correct because partitioning the 'orders' table by 'status' and 'order_date' can significantly reduce the amount of data scanned, as queries often filter on these columns. With 80% of orders being 'completed', partitioning by status allows queries for non-completed statuses to skip most rows, and range partitioning by order_date (e.g., monthly) further limits scans to relevant time periods. Adding covering indexes on common query patterns (e.g., (status, order_date, customer_id)) can make these partition scans index-only. Option B (read replicas) offloads read traffic but does not fix the slow queries themselves—they would still perform full scans on the replicas. Option C (caching) helps with repeated queries but not with ad-hoc analytical scans that still hit the database. Option D (vertical scaling) provides temporary relief but does not address the root cause of unnecessary full table scans.

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 'orders' table by 'status' and 'order_date' and create covering indexes on common query patterns.

    Why this is correct

    Partitioning reduces the data scanned, and covering indexes speed up queries without accessing the table.

    Related concept

    Read the scenario before looking for a memorised answer.

  • ✗

    Create multiple read replicas and distribute read traffic.

    Why it's wrong here

    Read replicas offload read traffic but each replica still executes the same slow queries.

  • ✗

    Implement an in-memory caching layer using Amazon ElastiCache for frequently accessed data.

    Why it's wrong here

    Caching helps with repeated queries but not with the broad range of queries filtering on different date ranges.

  • ✗

    Upgrade the RDS instance to a larger instance class with more vCPUs and memory.

    Why it's wrong here

    Scaling up provides temporary relief but does not fix the full table scan issue.

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 company's IT admin needs to give a contractor read-only access to production logs without sharing account credentials. Using role-based access control (RBAC) and temporary scoped permissions — not a permanent shared password — is the correct pattern. Questions like this test whether you can apply least-privilege access across cloud identity services.

What to study next

Got this wrong? Here's your next step.

Identify which DBS-C01 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.

Related practice questions

Related DBS-C01 practice-question pages

Use these pages to review the topic behind this question. This is how one missed question becomes focused revision.

Workload-Specific Database Design practice questions

Practise DBS-C01 questions linked to Workload-Specific Database Design.

Deployment and Migration practice questions

Practise DBS-C01 questions linked to Deployment and Migration.

Management and Operations practice questions

Practise DBS-C01 questions linked to Management and Operations.

Monitoring and Troubleshooting practice questions

Practise DBS-C01 questions linked to Monitoring and Troubleshooting.

Database Security practice questions

Practise DBS-C01 questions linked to Database Security.

DBS-C01 fundamentals practice questions

Practise DBS-C01 questions linked to DBS-C01 fundamentals.

DBS-C01 scenario practice questions

Practise DBS-C01 questions linked to DBS-C01 scenario.

DBS-C01 troubleshooting practice questions

Practise DBS-C01 questions linked to DBS-C01 troubleshooting.

Practice this exam

Start a free DBS-C01 practice session

Short sessions build daily habit. Longer sessions build exam-day stamina. Try a timed session to simulate real conditions.

10 questions20 questions30 questions50 questionsTimed 30
DBS-C01 practice-test guide →Study guide →Browse all practice tests

FAQ

Questions learners often ask

What does this DBS-C01 question test?

Workload-Specific Database Design — This question tests Workload-Specific Database Design — Read the scenario before looking for a memorised answer..

What is the correct answer to this question?

The correct answer is: Partition the 'orders' table by 'status' and 'order_date' and create covering indexes on common query patterns. — Option A is correct because partitioning the 'orders' table by 'status' and 'order_date' can significantly reduce the amount of data scanned, as queries often filter on these columns. With 80% of orders being 'completed', partitioning by status allows queries for non-completed statuses to skip most rows, and range partitioning by order_date (e.g., monthly) further limits scans to relevant time periods. Adding covering indexes on common query patterns (e.g., (status, order_date, customer_id)) can make these partition scans index-only. Option B (read replicas) offloads read traffic but does not fix the slow queries themselves—they would still perform full scans on the replicas. Option C (caching) helps with repeated queries but not with ad-hoc analytical scans that still hit the database. Option D (vertical scaling) provides temporary relief but does not address the root cause of unnecessary full table scans.

What should I do if I get this DBS-C01 question wrong?

Identify which DBS-C01 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 →

How Courseiva writes practice questions · Editorial policy

Keep practising

More DBS-C01 practice questions

Browse all DBS-C01 questions →

Last reviewed: Jun 20, 2026

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.

Loading comments…

Sign in to join the discussion.

This DBS-C01 practice question is part of Courseiva's free Amazon Web Services 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 DBS-C01 exam.