The correct choice is to create a read replica of the RDS for PostgreSQL instance and run the analytical query on it. This works because read replicas use asynchronous replication from the source instance, allowing the replica to handle heavy I/O and long-running queries independently without any performance impact on the primary workload. On the AWS Certified Data Engineer Associate DEA-C01 exam, this scenario tests your understanding of offloading analytical queries to read replicas as a core RDS scaling pattern, often appearing in questions about separating reporting from production traffic. A common trap is to consider Multi-AZ failover or a larger instance type, but those address high availability or vertical scaling, not workload isolation. Remember the key distinction: Multi-AZ is for availability, read replicas are for offloading reads. A useful memory tip is “Replica for reads, Multi-AZ for meets” — meaning read replicas handle query offloading while Multi-AZ ensures the database stays up during failures.
DEA-C01 Data Store Management Practice Question
This DEA-C01 practice question tests your understanding of data store management. 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.
A company runs a multi-AZ Amazon RDS for PostgreSQL instance. They need to run a one-time analytical query that will take several hours and consume significant I/O. The query should not impact the primary workload. What should the data engineer do?
Clue words in this question
Noticing these words before you look at the options changes how you read each choice.
Clue: "primary"
Why it matters: Asks for the main purpose or function, not a secondary benefit. Eliminate answers that describe side-effects or partial functions.
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
Create a read replica of the RDS instance and run the query on the replica.
Option A is correct because creating a read replica of the RDS for PostgreSQL instance allows the analytical query to run on a separate database engine without affecting the primary workload. Read replicas in Amazon RDS use asynchronous replication from the source instance, so the replica can handle heavy I/O and long-running queries independently. This ensures the primary instance remains available for the production workload without performance degradation.
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.
✓
Create a read replica of the RDS instance and run the query on the replica.
Why this is correct
Read replica offloads read traffic from the primary.
Clue confirmation
The clue word "primary" in the question point toward this answer.
Related concept
Read the scenario before looking for a memorised answer.
✗
Run the query directly on the primary instance during off-peak hours.
Why it's wrong here
The query will still impact primary performance.
✗
Increase the instance size to handle the load.
Why it's wrong here
Does not isolate the query impact.
✗
Enable Multi-AZ and run the query on the standby instance.
Why it's wrong here
Multi-AZ standby is not accessible for reads.
Common exam traps
Common exam trap: answer the scenario, not the keyword
The trap here is that candidates often confuse the Multi-AZ standby instance with a read replica, assuming the standby can be used for queries, but in Amazon RDS, the standby is only for high availability and is not accessible for read operations.
Detailed technical explanation
How to think about this question
Amazon RDS read replicas use PostgreSQL's native streaming replication to maintain an asynchronous copy of the database. The replica can be promoted to a standalone instance if needed, and it supports its own connection endpoints, allowing read-heavy workloads to be offloaded. Under the hood, the replica applies WAL (Write-Ahead Log) changes from the primary, so there is a small replication lag, but for a one-time analytical query, this lag is acceptable and does not affect the primary's performance.
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.
What to study next
Got this wrong? Here's your next step.
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
Data Store Management — This question tests Data Store Management — Read the scenario before looking for a memorised answer..
What is the correct answer to this question?
The correct answer is: Create a read replica of the RDS instance and run the query on the replica. — Option A is correct because creating a read replica of the RDS for PostgreSQL instance allows the analytical query to run on a separate database engine without affecting the primary workload. Read replicas in Amazon RDS use asynchronous replication from the source instance, so the replica can handle heavy I/O and long-running queries independently. This ensures the primary instance remains available for the production workload without performance degradation.
What should I do if I get this DEA-C01 question wrong?
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
Are there clue words in this question I should notice?
Yes — watch for: "primary". Asks for the main purpose or function, not a secondary benefit. Eliminate answers that describe side-effects or partial functions.
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 DEA-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 DEA-C01 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.