Objective 3.4CLF-C02

3.4 Identify AWS database services.

Objective 3.4 sits in Cloud Technology and Services, which carries 34% of the Cloud Practitioner exam. The questions below are original, written from the official objective title above, and each explanation cites the AWS page it rests on.

Objective title verbatim from the official objectives. AWS exam page

A worked example

Shown solved, with the whole explanation open: this is what every question here carries.

Cloud Technology and ServicesModerate

A shopping cart needs single-digit millisecond reads at any scale, with no servers to patch and no capacity to provision. Which database fits?

Correct.

The concept

Choosing a data store starts with the access pattern, not the feature list. Predictable lookups by key at high volume and rich ad hoc querying pull toward different engines and different operating models.

Why this answer

A serverless NoSQL store answers key-based lookups in the same few milliseconds whether ten people or a hundred million are using it, with no instances, versions or maintenance windows in the picture.

  • ARDS runs on DB instances you size, and it schedules maintenance windows. It also gives you joins that a cart lookup has no use for.
  • Correct. DynamoDB is a serverless, fully managed, distributed NoSQL database with single-digit millisecond performance at any scale.
  • CAurora is a relational engine compatible with MySQL and PostgreSQL. Its storage grows on its own, but you still pick instance classes.
  • DRedshift is a data warehouse built for analytical queries over large datasets. A point lookup on a cart is the opposite workload.
Read the sourceAWS Docs: What is Amazon DynamoDB
Source-cited
dynamodbnosqlserverless

Now you: objective 3.4 questions

No account needed. The explanation opens when you answer.

Sample question 1 of 3

Cloud Technology and ServicesModerate

A team moves a PostgreSQL database from EC2 to Amazon RDS. Which task stops being theirs after the move?

Sample question 2 of 3

Cloud Technology and ServicesHard

A team weighs Aurora against RDS for PostgreSQL for a database that keeps growing. How does Aurora handle the storage volume?

Sample question 3 of 3

Cloud Technology and ServicesHard

A reporting feature joins five normalized tables and runs ad hoc SQL. Why is DynamoDB the wrong choice for it?

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Read the sources

These are the official pages the questions above cite. Reading them is studying the objective from the primary source, which is what the explanations point you toward anyway.

More objectives in Cloud Technology and Services