RDS supported engines in AWS - Practice Problems & Coding Challenges

Challenge - 5 Problems

🧠 Conceptual

intermediate

Identify the supported RDS engine for a relational database

Which of the following is a supported engine type for Amazon RDS that is designed for relational databases?

A Amazon Neptune

B Amazon DynamoDB

C Amazon ElastiCache

D Amazon Aurora

💡 Hint

Think about engines that support SQL and relational data models.

Amazon Aurora is a relational database engine supported by Amazon RDS. DynamoDB is a NoSQL database, ElastiCache is for caching, and Neptune is a graph database.

🧠 Conceptual

intermediate

Select the RDS engine that supports PostgreSQL compatibility

Which Amazon RDS engine provides compatibility with PostgreSQL?

A Amazon Aurora PostgreSQL

B Amazon DocumentDB

C Amazon Redshift

D Amazon Aurora MySQL

💡 Hint

Look for the engine name that includes PostgreSQL.

Amazon Aurora PostgreSQL is an RDS engine compatible with PostgreSQL. Aurora MySQL is compatible with MySQL, Redshift is a data warehouse, and DocumentDB is for document databases.

❓ Architecture

advanced

Determine the best RDS engine for a multi-AZ high availability setup

You need a managed database with automatic failover across multiple availability zones. Which RDS engine supports this feature natively?

A Amazon RDS for MariaDB

B Amazon Aurora

C Amazon RDS for Oracle Standard Edition

D Amazon RDS for SQL Server Express Edition

💡 Hint

Consider engines designed for high availability and fault tolerance.

Amazon Aurora supports multi-AZ deployments with automatic failover built-in. Other engines support multi-AZ but may have limitations or require additional configuration.

❓ security

advanced

Identify which RDS engine supports encryption at rest using AWS KMS

Which Amazon RDS engine supports encryption at rest using AWS Key Management Service (KMS)?

A Amazon DynamoDB

B Amazon ElastiCache for Redis

C Amazon RDS for MySQL

D Amazon S3

💡 Hint

Focus on RDS engines and their encryption capabilities.

Amazon RDS for MySQL supports encryption at rest using AWS KMS. ElastiCache, DynamoDB, and S3 are different services with their own encryption methods.

❓ service_behavior

expert

Predict the behavior when launching an unsupported engine version in RDS

What happens if you try to launch an Amazon RDS instance with an engine version that is not supported by AWS?

A The launch request fails with an error indicating unsupported engine version.

B The instance launches but automatically upgrades to the nearest supported version.

C The instance launches but runs in a degraded mode with limited features.

D The instance launches successfully and AWS notifies you later about the unsupported version.

💡 Hint

Consider AWS's approach to unsupported configurations.

AWS prevents launching RDS instances with unsupported engine versions by failing the request immediately to avoid unstable or unsupported environments.

Practice

1. Which of the following database engines is supported by AWS RDS?

easy

A. MySQL

B. MongoDB

C. Cassandra

D. Redis

Solution

1. Step 1: Recall AWS RDS supported engines

   AWS RDS supports popular relational database engines like MySQL, PostgreSQL, Oracle, SQL Server, and Aurora.

2. Step 2: Identify which option matches supported engines

   Among the options, only MySQL is a supported RDS engine. MongoDB, Cassandra, and Redis are not supported by RDS but by other AWS services.

3. Final Answer:

   MySQL -> Option A

4. Quick Check:

   RDS supports MySQL = A [OK]

Hint: Remember RDS supports relational engines like MySQL, not NoSQL [OK]

Common Mistakes:

• Confusing NoSQL databases as RDS engines
• Assuming Redis is supported by RDS
• Thinking Cassandra is supported by RDS

2. Which of the following is the correct way to specify the engine when creating an RDS instance using AWS CLI?

easy

A. --engine mongodb

B. --engine mysql

C. --engine redis

D. --engine cassandra

Solution

1. Step 1: Understand AWS CLI engine parameter

   The AWS CLI uses the parameter --engine to specify the database engine when creating an RDS instance.

2. Step 2: Identify valid engine names

   Valid engine names include mysql, postgres, oracle, sqlserver, aurora. MongoDB, Redis, and Cassandra are not valid for RDS engine parameter.

3. Final Answer:

   --engine mysql -> Option B

4. Quick Check:

   Correct engine name for MySQL is mysql [OK]

Hint: Use lowercase engine names like mysql, not unsupported ones [OK]

Common Mistakes:

• Using unsupported engines like mongodb or redis
• Capitalizing engine names incorrectly
• Confusing engine parameter with instance type

3. Given the following AWS CLI command to create an RDS instance:

aws rds create-db-instance --db-instance-identifier mydb --engine postgres --allocated-storage 20 --db-instance-class db.t3.micro --master-username admin --master-user-password secret123

What database engine will this RDS instance use?

medium

A. SQL Server

B. MySQL

C. Oracle

D. PostgreSQL

Solution

1. Step 1: Analyze the --engine parameter in the command

   The command specifies --engine postgres, which corresponds to PostgreSQL.

2. Step 2: Match engine parameter to database engine

   Postgres is the short name for PostgreSQL, a supported RDS engine.

3. Final Answer:

   PostgreSQL -> Option D

4. Quick Check:

   --engine postgres means PostgreSQL [OK]

Hint: Look for --engine value to identify the database engine [OK]

Common Mistakes:

• Confusing postgres with MySQL
• Assuming default engine is MySQL
• Ignoring the --engine parameter

4. You tried to create an RDS instance with the command:

aws rds create-db-instance --db-instance-identifier testdb --engine mongo --allocated-storage 20 --db-instance-class db.t3.micro --master-username admin --master-user-password secret123

But it failed. What is the most likely reason?

medium

A. The master username is missing

B. The allocated storage is too low

C. The engine name 'mongo' is not supported by RDS

D. The instance class db.t3.micro is invalid

Solution

1. Step 1: Check the engine parameter validity

   The engine parameter is set to 'mongo', which is not a supported RDS engine. MongoDB is not supported by RDS.

2. Step 2: Verify other parameters

   Allocated storage of 20 GB and instance class db.t3.micro are valid. Master username is provided.

3. Final Answer:

   The engine name 'mongo' is not supported by RDS -> Option C

4. Quick Check:

   Unsupported engine name causes failure [OK]

Hint: Check engine names carefully; unsupported names cause errors [OK]

Common Mistakes:

• Assuming MongoDB is supported by RDS
• Blaming storage size or instance class incorrectly
• Overlooking the exact error message

5. You want to migrate an on-premises Oracle database to AWS RDS. Which RDS engine should you choose to ensure compatibility and minimal changes?

hard

A. Oracle

B. PostgreSQL

C. Aurora MySQL

D. SQL Server

Solution

1. Step 1: Identify the source database engine

   The source is an on-premises Oracle database, so compatibility is key.

2. Step 2: Choose the matching RDS engine

   AWS RDS supports Oracle as a managed engine, which ensures compatibility and minimal changes during migration.

3. Step 3: Consider other options

   Aurora MySQL, PostgreSQL, and SQL Server are different engines and would require significant changes.

4. Final Answer:

   Oracle -> Option A

5. Quick Check:

   Match source engine to RDS engine for smooth migration [OK]

Hint: Pick the same engine type for easy migration [OK]

Common Mistakes:

• Choosing Aurora MySQL for Oracle migration
• Assuming PostgreSQL is compatible with Oracle
• Ignoring migration compatibility