Databases on AWS

Question 1

Name the 6 types of RDS’s in AWS

Answer 1

1. SQL Server 2. Oracle 3. My SQL Server 4. PostgreSQL 5. Aurora 6. MariaDB

Question 2

What are the two key features of RDS?

Answer 2

Multi AZ for DR and Read replicas for performance

Question 3

Are key value pairs found in RDS or Non Relational DB’s?

Answer 3

Non relational DB’s

Question 4

What is data warehousing used for?

Answer 4

business intelligence and pulling in very large and complex data sets

Question 5

What is Amazon’s Data Warehouse Solution called?

Answer 5

Red Shift

Question 6

What is Amazon’s noSQL DB solution called?

Answer 6

DynamoDB

Question 7

What do RDS’s run on?

Answer 7

Virtual Machines (EC2 instances)

Question 8

Who is responsible for patching of RDS’s?

Answer 8

Amazon

Question 9

True of false: RDS is Serverless

Answer 9

False, with the only exception of Aurora Serverless

Question 10

What are the two types of backups for RDS?

Answer 10

Automated and Database Snapshots

Question 11

T or F: Multi AZ for RDS will give you an exact copy of your production DB in another AZ

Answer 11

True

Question 12

Why use Read Replicas?

Answer 12

It improves performance of your DB

Question 13

What must you have turned on in order to deploy a read replica?

Answer 13

Automatic backups

Question 14

Where is DynamoDB stored?

Answer 14

SSD Storage

Question 15

How many data centers is Dynamo DB spread across?

Answer 15

3

Question 16

Difference between Eventual Consistent Read and Strongly Consistent Read for DyanmoDB

Answer 16

Eventual means usually read within a second and Strongly is less than a second

Question 17

What is DynamoDB Accelerator (DAX)

Answer 17

fully managed, highly available, in memory cache. This will reduce request times from milliseconds to microseconds.

Question 18

Why would a developer want to use DAX?

Answer 18

So they don’t have to manager the caching logic

Question 19

What are transactions in DynamoDB?

Answer 19

Fulfilling orders. DynamoDB prepares two underlying reads or writes

Question 20

What are streams in DynamoDB?

Answer 20

time ordered sequence of item level changes in a table

Question 21

What are shards in DynamoDB?

Answer 21

Groups of stream records.

Question 22

What allows you to configure data migration logic from one DB to another?

Answer 22

Database Migration Service (DMS)

Question 23

What is AWS’s data warehousing option?

Answer 23

Redshift

Question 24

In what two options can you configure Redshift?

Answer 24

Single or multi node

Question 25

In a multi node configuration in Redshift, what are the types of nodes?

Answer 25

Leader node and Compute Node

Question 26

Explain leader nodes and compute nodes

Answer 26

Leader manages client connections and receives queries. Compute stores data and perform queries and computation. You can have up to 128 compute nodes

Question 27

What feature of Redshift allows it to use less space?

Answer 27

Advanced compression

Question 28

What is the benefit of using Aurora?

Answer 28

relational DB engine that combines speed and availability of high end commercial DB's

Question 29

How is Aurora self healing?

Answer 29

data block and disks are continuously scanned for errors and repaired automatically

Question 30

3 types of Aurora replicas

Answer 30

1. Aurora replica (in region, automated failover) 2. MySQL read replica (cross region, no automated failover) 3. PostgresQL

Question 31

What is Aurora Serverless and when would you use it?

Answer 31

on demand, autoscaling config for MySQL and PostgreSQL compatible editions of Aurora. Used for infrequent or unpredictable workloads

Question 32

What is Elasticache?

Answer 32

web service for deploying, operating and scaling and in memory cache in the cloud

Question 33

What are the 2 open source caching engines that are options in Elasticache?

Answer 33

Memcached & Redis

Question 34

When to use Memcached vs Redis

Answer 34

Memcached - simple and easy to start / Redis - need advanced data type, multi AZ, or ranking and sorting data sets

Question 35

Types of Data Migration Services (DMS) migrations

Answer 35

1. homogenous migrations (DB's of the same type 2. heterogenous migrations (one type of B to another)

Question 36

What must you use for heterogenous DMS migrations?

Answer 36

AWS Schema Conversion tool

Question 37

What is Amazon EMR?

Answer 37

big data platform for processing vast amounts of data using open source tools

Question 38

What is the central component of Amazon EMR?

Answer 38

The cluster, which is a collection of EC2 instances

Question 39

What are the node types in Amazon EMR and what do they do?

Answer 39

1. Master Node - manages the cluster. Every cluster has one 2. Core Node - Runs tasks and stores data in Hadoop Distributed File System ( HDFS) 3. Task Node - runs tasks but does not store data in HDFS. These are optional

Question 40

Where is log data stored at by default in Amazon EMR?

Answer 40

The master node

Question 41

What happens to I/O operations of a single AZ RDS instance during a DB snapshot or backup?

Answer 41

I/O may be briefly suspended while backup process initializes and you may experience brief period of elevated latency

Question 42

T or F: You can RDP or SSH into an RDS instance

Answer 42

F

Question 43

T or F: RDS Reserved Instances are available for multi AZ deployments

Answer 43

T

Question 44

What is the max value for RDS backup retention periods?

Answer 44

35 days

Question 45

What storage option is recommended if you want to run a DB on an EC2 instance?

Answer 45

EBS

Question 46

Default port number for MySQL installation

Answer 46

3306

Question 47

Which AWS DB platform is most suitable for Online Transaction Processing (OLTP)

Answer 47

RDS

Question 48

Yes or No: Is there a data transfer charge incurred when replicating data from your primary RDS instance to your secondary?

Answer 48

No

Question 49

T or F: DynamoDB is a non relational DB

Answer 49

T

Question 50

T or F: When you add a rule to a RDS DB security group, you must specify a port number or protocol

Answer 50

F