DP-203 Design and implement data storage Practice Question
You are designing a storage solution for a financial services company that uses Azure SQL Database. The database contains a table with sensitive customer data, including credit card numbers. Regulatory requirements mandate that the credit card numbers must be encrypted at rest and in use, and only authorized applications should be able to decrypt them. You need to implement a solution that allows encryption keys to be managed in Azure Key Vault. What should you use?
⚠ Common exam trap
It's easy for candidates to confuse encryption at rest with encryption in use, leading to the selection of TDE or masking when the requirement is for client-side encryption.
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
✓
Always Encrypted with column master keys stored in Azure Key Vault.
Always Encrypted encrypts sensitive columns on the client side, ensuring data is protected both at rest and in use. By storing column master keys in Azure Key Vault, key management is centralized and access is restricted to authorized applications. This satisfies the requirements for encryption in use and authorized decryption, which other options do not provide.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
Row-level security (RLS) with a security policy on the customer table.
Why it's wrong here
Row-level security restricts which rows a user can access based on a predicate, but it does not encrypt data. The data remains unencrypted at rest and in use, and RLS does not provide key management through Azure Key Vault. This option addresses access control, not encryption, and therefore does not meet the regulatory requirements.
- ✓
Always Encrypted with column master keys stored in Azure Key Vault.
Why this is correct
Always Encrypted protects data at rest and in use by encrypting sensitive columns on the client side, so the database engine never sees plaintext. Column master keys can be stored in Azure Key Vault, and only client applications with access to those keys can decrypt the data. This meets the requirements for encryption in use and authorized application access.
- ✗
Dynamic data masking on the credit card number column.
Why it's wrong here
Dynamic data masking hides data from non-privileged users at query time but does not encrypt the data at rest or in use. The underlying data remains plaintext in the database, and users with sufficient privileges can see the unmasked values. It also does not integrate with Azure Key Vault for key management, so it fails the encryption requirements.
- ✗
Transparent Data Encryption (TDE) with service-managed keys.
Why it's wrong here
TDE encrypts data at rest, including backups, but it does not encrypt data in use or provide column-level encryption. With service-managed keys, the keys are not stored in Azure Key Vault, so this does not meet the requirement for key management in Key Vault. TDE also does not restrict decryption to authorized applications.
Go deeper
Related to this question
About these practice questions
One of 509 original DP-203 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 and reviewed by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
Last reviewed September 2026 · checked against the official Microsoft exam blueprint
This DP-203 practice question is part of Courseiva's free Microsoft 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 DP-203 exam.