Free CLF-C02 practice questions: AWS databases overview

AWS builds a database per job, and the exam checks you can pick the right one. Seven questions across the database portfolio — 2026 edition.

Here are 7 typical AWS database questions in the exam's own style — free, with the answer explained, no sign-up.

Straight to the 7 free questions ↓

AWS does not sell one database; it sells a database per job. The CLF-C02 tests whether you can read a workload and pick the right one from a small portfolio. There is no depth to master — only the fit between a described need and a purpose-built service.

The portfolio, by job

Amazon RDS — a managed relational database (tables, rows, SQL), with AWS running the operations. Amazon Aurora is AWS’s own MySQL- and PostgreSQL-compatible relational engine, offered through RDS for higher performance and availability.
Amazon DynamoDB — a managed NoSQL key-value database, built for fast, consistent performance at massive scale.
Amazon Redshift — a data warehouse for complex analytical queries over large datasets.
Amazon ElastiCache — an in-memory cache (Redis or Memcached) that speeds up reads by keeping hot data in memory, usually in front of a database.

The idea underneath: purpose-built databases

AWS follows a purpose-built approach — relational, NoSQL, analytics and caching are genuinely different jobs, so each gets a database designed for it. That is the answer to “why so many databases”: fit, not branding. Once you accept that, the questions become a matching exercise.

Reading the workload

The scenario always points at one service:

Relational, SQL, transactions → RDS (or Aurora when it names MySQL/PostgreSQL compatibility or high performance).
Schema-less, key-value, huge scale, millisecond lookups → DynamoDB.
Analytics, reporting, “data warehouse,” large historical data → Redshift.
“Speed up reads,” “cache,” “in-memory” → ElastiCache.

Read for those signals — “flexible schema,” “analytics,” “cache” — and the service follows. The distractors are always other real databases from the same list, offered for the wrong job.

How to use the questions below

Answer each one before opening the explanation, then read past the correct letter to why the other three fail. The whole skill is matching the shape of the data and the job to the one purpose-built service that fits, and the reasoning below drills exactly that.

The AWS purpose-built database services matched to workloads: Amazon RDS and Aurora for relational data, Amazon DynamoDB for NoSQL key-value at scale, Amazon Redshift for data-warehouse analytics, and Amazon ElastiCache for in-memory caching to speed up reads.

7 free CLF-C02 practice questions

Answers and explanations — no email wall

CLF-C02 Question 1 of 7

A company needs a fully managed relational database with tables, rows and SQL. Which service fits?

Answer: A — Amazon RDS

Amazon RDS is the managed relational database service — tables, rows and SQL, with AWS handling the operations. Why not the others: DynamoDB is NoSQL, a different data model. Redshift is a data warehouse for analytics, not a general transactional database. ElastiCache is an in-memory cache, not a primary database. Relational and managed points to RDS.

CLF-C02 Question 2 of 7

A workload needs a managed NoSQL key-value database with single-digit-millisecond performance at very large scale. Which service fits?

Answer: A — Amazon DynamoDB

Amazon DynamoDB is the managed NoSQL key-value database, built for consistent low-latency performance at scale. Why not the others: RDS and Aurora are relational. Redshift is an analytics data warehouse. When a question stresses NoSQL, key-value, and scale, it is describing DynamoDB.

CLF-C02 Question 3 of 7

A team wants to run complex analytical queries across very large volumes of historical data — a data warehouse. Which service fits?

Answer: A — Amazon Redshift

Amazon Redshift is AWS's data warehouse, designed for analytical queries over large datasets. Why not the others: DynamoDB is for fast key-value operations, not heavy analytics. RDS is for transactional relational workloads. ElastiCache is a cache. 'Data warehouse' and 'analytics over large data' is the Redshift signal.

CLF-C02 Question 4 of 7

An application's database reads are slow, and the team wants to cache frequently accessed data in memory to speed them up. Which service fits?

Answer: A — Amazon ElastiCache

Amazon ElastiCache provides in-memory caching (Redis or Memcached) to serve frequently accessed data quickly and take load off the database. Why not the others: RDS and DynamoDB are databases, not caches (though a cache often sits in front of them). S3 is object storage. An in-memory cache to speed up reads is ElastiCache.

CLF-C02 Question 5 of 7

Which service is a MySQL- and PostgreSQL-compatible relational database built by AWS for higher performance and availability?

Answer: A — Amazon Aurora

Amazon Aurora is AWS's relational database engine, compatible with MySQL and PostgreSQL, offered through RDS with higher performance and availability. Why not the others: DynamoDB is NoSQL, Redshift is a data warehouse, and ElastiCache is a cache. Aurora is the relational option that is MySQL/PostgreSQL-compatible.

CLF-C02 Question 6 of 7

A workload has flexible, schema-less data and needs simple, fast lookups at massive scale. Which type of database is the better fit?

Answer: A — A NoSQL database such as Amazon DynamoDB

Flexible, schema-less data with simple lookups at scale is the classic NoSQL profile, and DynamoDB is AWS's managed NoSQL database. Why not the others: a relational database expects a fixed schema and relationships. A data warehouse is for analytics, not fast individual lookups. A cache accelerates reads but is not the primary store. Schema-less and scale means NoSQL.

CLF-C02 Question 7 of 7

Why does AWS offer several different database services rather than a single one?

Answer: A — Because different data models and workloads are best served by purpose-built databases

AWS follows a purpose-built approach: relational, NoSQL, analytics and caching are genuinely different jobs, each served best by a database designed for it. Why not the others: the services are not identical rebrands, the goal is fit rather than upselling, and this is not about retiring old databases. Matching the workload to the right purpose-built database is the whole point — and the whole exam skill.

That is exactly how every question in the course works — answer, explanation, why-not. The real set continues in the practice player: 10 free questions, no sign-up.

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Those 7 questions were the start.

The exam does not test whether you recognise a term — it tests whether you can rule out three plausible answers under time pressure. That is what the explanations above are for, and there are 390 more questions built exactly like them.

Collecting questions yourself

Scattered across forums, of unknown age
Answer keys without reasoning
No idea which domain you are weak in

Practising with a system

390 questions in 6 full tests, CLF-C02 (2026)
Every option explained — including the wrong ones
Readiness per exam domain, and drills for your weakest

Start free — 10 questions

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Frequently asked questions

Is this the current CLF-C02 format?

Yes — these questions follow the CLF-C02 exam guide (2026 edition). Databases sit in the Cloud Technology and Services domain, the largest on the exam at 34%, and 'which database for which need' is a dependable pattern within it.

Are these real exam questions?

No. They are our own questions, written in the style and difficulty of the exam. Reproducing real exam items violates the AWS certification agreement and can get your certification revoked, and a memorised item teaches you nothing about the one you have not seen.

How is this different from the Amazon RDS page?

The RDS page goes deep on one service — what 'managed' means and the Multi-AZ-versus-read-replica distinction. This page is the wider view: choosing between RDS, DynamoDB, Redshift, ElastiCache and Aurora for a described workload.

What is the quickest way to pick the right database?

Read the data and the job. Relational with SQL points to RDS or Aurora. Schema-less key-value at scale points to DynamoDB. Analytics over large data points to Redshift. Speeding up reads with in-memory data points to ElastiCache. Match the shape to the service.

Updated for CLF-C02 (July 2026). The sample questions above are our own work in the style of the exam — not real exam items. The exam itself is set and marked by the certification body.