DBS-C01 Database Security Practice Question
A company is using Amazon RDS for PostgreSQL and needs to implement column-level encryption for sensitive data. The application must be able to encrypt and decrypt data transparently. Which approach should be taken?
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
✓
Install the pgcrypto extension on the RDS instance and use its functions to encrypt data at the column level.
Pgcrypto is a PostgreSQL extension that provides column-level encryption functions, allowing the application to encrypt and decrypt data transparently at the column level. Option A is incorrect because RDS encryption at rest encrypts the entire database storage, not individual columns. Option B is incorrect because using AWS Lambda would require application modifications and introduce additional latency. Option C is incorrect because AWS KMS is a key management service, not a direct column-level encryption solution for databases, and using its APIs would require building encryption logic in the application.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
Enable RDS encryption at rest using a KMS key, which will automatically encrypt all columns.
Why it's wrong here
Encryption at rest encrypts the entire storage, not columns individually.
- ✗
Use AWS Lambda to encrypt data before writing to the database and decrypt after reading.
Why it's wrong here
Requires application changes and adds latency.
- ✗
Use the AWS KMS Encrypt and Decrypt APIs directly in the application code.
Why it's wrong here
KMS is not designed for column-level encryption in RDS; it's used for key management.
- ✓
Install the pgcrypto extension on the RDS instance and use its functions to encrypt data at the column level.
Why this is correct
pgcrypto provides transparent column-level encryption.
Quick reference
Cloud Service Model Comparison
| Model | You Manage | Provider Manages | Examples |
|---|---|---|---|
| IaaS | OS, runtime, apps, data | Hardware, hypervisor, networking | EC2, Azure VMs, GCP Compute Engine |
| PaaS | Apps and data | OS, runtime, middleware, hardware | Elastic Beanstalk, Azure App Service |
| SaaS | Data and settings only | Everything else | Microsoft 365, Salesforce, Workday |
| FaaS / Serverless | Function code only | Infra, scaling, runtime | Lambda, Azure Functions, Cloud Run |
| CaaS | Containers and apps | Kubernetes, OS, hardware | EKS, AKS, GKE |
Go deeper
Related to this question
About these practice questions
One of 1,663 original DBS-C01 practice questions on Courseiva, each with a full explanation and wrong-answer analysis — not exam dumps or protected exam content. Learn why practice questions differ from exam dumps →
JA
Written by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
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.