Databases

Question 1

List the types of AWS databases

Answer 1

RDS & Aurora: Relational
DynamoDB: NoSQL
ElastiCache: In-memory; Redis & Memcached
Neptune: Graph
DocumentDB: for Documents; supports MongoDB

Question 2

What can Aurora be used for?

Answer 2

MySQL
PostgreSQL

Question 3

What is ElastiCache?

Answer 3

A fully managed (Saas) in-memory datastore
Supports 2 engines: Redis and Memcached
Data can be lost
Low latency
Enables scaling and replicas to meet demand

Question 4

What is Neptune and what is it good for?

Answer 4

A fully managed graph database.
Good for highly connected datasets like social media networks.

Question 5

What would you use to migrate an on-premises Oracle database to the cloud?

Answer 5

RDS

Question 6

What would you use to migrate an on-premises Postgres database to the cloud?

Answer 6

RDS or Aurora

Question 7

How would you alleviate database load for data that is accessed often?

Answer 7

ElastiCache

Question 8

How would you process large sets of user profiles and social interactions?

Answer 8

Neptune

Question 9

Name a NOSQL database fast enough to handle millions of db requests per second.

Answer 9

DynamoDB

Question 10

How can you operate MongoDB workloads at scale?

Answer 10

DocumentDB (it mimics MongoDB)

Question 11

How would you do database as IaaS?

Answer 11

Spin up your own EC2 instance and deploy a database onto it

Question 12

Which database would be PaaS?

Answer 12

RDS

Question 13

Which databases would offer a SaaS approach?

Answer 13

DynamoDB
Elasticache
Redshift

Question 14

RDS

Answer 14

• a PaaS relational database system
• can deploy across multiple AZ’s
• It launches into a VPC
• uses 2 volume types: SSD, IOPS SSD
• Platforms: MySQL, PostGres, Oracle, MariaDB, SQLServer, Amazon Aurora

Question 15

What is Amazon DMS?

Answer 15

Database Migration Service
Moves data into AWS
Only pay for the compute time of the migration

Question 16

What are the features of DynamoDB?

Answer 16

Fully managed SaaS database service
NoSQL, not relational
Both key-value and document
auto-scaling
More than 10 trillion requests per day; 20 million per second

Question 17

What are the DynamoDB use cases?

Answer 17

Scale without excessive maintenance
If you want serverless applications
Low latency is key
Data Models without BLOB storage (that won’t work well)

Question 18

What are use cases for ElastiCache?

Answer 18

You have a database like DynamoDB and want to add a cache layer
Session storage for Web apps (Redis)

Question 19

What is Redshift?

Answer 19

Amazon’s data warehouse service
It does analytics
Petabyte scale
Can fully encrypt
Provides isolation with a VPC

Question 20

What is Redshift Spectrum?

Answer 20

• Can query exabytes of data within S3
• Fast, complex analysis on objects stored on the AWS cloud.
• Can perform SQL queries on data stored in S3 buckets.

Question 21

What is MemoryDB?

Answer 21

A Redis-compatible in-memory database
Good to use as a primary database

Question 22

What is Timestream?

Answer 22

A serverless time series database service
Example: Sensor data: capturing data at specific times. Like you have a temperature gauge and want to find out the avg temp for last Wednesday

Question 23

What would you suggest for a company that has a MySQL db, wants to launch a new Web App with it, but needs direct access to the virtual server that MySQL is running on?

Answer 23

EC2 - have an EC2 instance and add a MySQL database to it

Question 24

What database would you use for a gaming system that requires low latency and up to 1 million players?

Answer 24

DynamoDB