Databases

Question 1

RDS uses what type of processing and database engines?

Answer 1

Use for OLTP. SQL Server, MySQL, PostgreSQL, Oracle, Aurora, MariaDB

Question 2

DynamoDB is what type of DB service?

Answer 2

NoSQL

Question 3

Redshift uses what type of processing?

Answer 3

OLAP

Question 4

Elasticache

Answer 4

In-memory caching. Memcached and Redis

Question 5

What is the use case for Multi-AZ?

Answer 5

Used for failover, data synchronously replicated

Question 6

What is the use case for Read Replicas?

Answer 6

Used for frequent reads, up to 5 read replicas

Question 7

Aurora scaling holds how many copies?

Answer 7

2 copies of your data in minimum 3 AZs, so 6 copies of your data.

Question 8

DynamoDB vs RDS

Answer 8

DynamoDB has push button scaling, so scale your database on the fly. RDS - need to use bigger instance or add read replica

Question 9

DynamoDB properties

Answer 9

stored on SSD storage, spread across 3 geographically distinct data centers, eventual consistent reads (default), strongly consistent reads

Question 10

Redshift configuration

Answer 10

Single node (160 Gb), Multi-Node

Question 11

Multi-Node

Answer 11

Leader node (manages client connections and receives queries)
Compute node (store data and perform queries and computations). Up to 128 compute nodes

Question 12

Aurora handle the loss of up to how many copies of data before writes are affected?

Answer 12

Designed to handle the loss of up to 2 copies of data w/o affecting writes,

Question 13

Aurora handle the loss of up to how many copies of data before reads are affected?

Answer 13

3 copies w/o affecting reads.

Question 14

What RDS engine is self healing?

Answer 14

Aurora

Question 15

What type of replicas are available with Aurora?

Answer 15

Aurora replicas and MySQL read replicas