Udemy lecture 7: Databases & analytics

Question 1

What is a relational database?

Answer 1

Relational database is when you make a link to multiple tables (ex. a student made 1 table with student ID, Dept ID, Name, Email, & then a second table was made linking to the first one where in the second table it starts with Dept ID, then gives futher information) (think of it like an excel sheet)

Question 2

In relational databases it uses the __________ language to perform queries or lookups

Answer 2

SQL (Whenever you hear SQL think of relational databases)

Question 3

______________ databases are nonrelational databases

Answer 3

NoSQL

Question 4

____________ databases are purpose built for specific data models & have flexible schemas for building modern applications

Answer 4

NoSQL

Question 5

What are some benefits of NoSQL databases?

Answer 5

• Flexible- easy to evolve data model
• Scalability- designed to scale out by using distributed clusters
• High-performance- optimized for a specific data model
  -Highly functional- types optimized for data model

Question 6

What does JSON stand for?

Answer 6

Javascript object notation

Question 7

NoSQL can have its data in _________ format

Answer 7

JSON

Question 8

Data can be _______ in the JSON format

Answer 8

Nested (storing data using in a structure way, but the fields (information) can change over time so have to change that information (support for new types of arrays))

Question 9

What is AWS responsibility related to databases

Answer 9

• Responsible for the entire database in terms of patching
• Automated backup & restore, operations, upgrades
• Monitoring, alerting

-AWS offers to manage different databses

Question 10

______ is a relational database

Answer 10

RDS

Question 11

What does RDS stand for?

Answer 11

Relational database service

Question 12

What is a Relational database service?

Answer 12

A managed database service for database that will use SQL as a query language, & it will allow you to create databases in the cloud that will be managed by AWS

Question 13

_________ is a proprietary database from AWS

Answer 13

Aurora

Question 14

What are the advantages to using RDS than deploying a database on EC2?

Answer 14

• Automated provisioning, OS patching
• Continuous backups & restore to specific timestamps (point-in-time restore)!
  -Monitoring dashboards
  -Read replicas for improved read performance
  -Multi-AZ setup for DR (disaster recovery)
• Maintenance windows for upgrades
• Scaling capability (vertical & horizontal)

Question 15

With RDS databases you can’t connect ________ to it

Answer 15

SSH

Question 16

What are the two kinds of database technologies that aurora supports?

Answer 16

1. PostgreSQL
2. MySQL

Question 17

Aurora is supposed to be _________ optimized to yield better performances

Answer 17

Cloud

Question 18

Aurora storage grows automatically from __________________

Answer 18

From 10 gigabytes to 128 terabytes

Question 19

__________ & ___________ are the two ways to create relational databases on AWS

Answer 19

RDS & Aurora (They are both managed & aurora is more cloud-native whereas RDS is going to be running on the technologies you know that is a managed service)

Question 20

The __________ option for Amazon Aurora is where the database instantiation is going to be automated

Answer 20

Serverless (also has auto scaling based on your usage)

Question 21

Both ________ & ___________ are supported as engines of aurora serverless database

Answer 21

PostgreSQL & MySQL

Question 22

Aurora serverless is great for _____________ workloads

Answer 22

Infrequent/unpredictable workloads

Question 23

If your see Aurora with no management overhead then think of ______________

Answer 23

Aurora serverless

Question 24

___________ can scale the read workload of your database

Answer 24

RDS read replicas (can create up to 15 replicas & data is only written to the main database)

Question 25

__________ is useful to have in case of AZ outage or main database has problems (high availability)

Answer 25

failover database (so its bascially multi AZ)

Question 26

In the ___________ data is only read/written to the main database & can only have one other AZ as a ________

Answer 26

Failover

Question 27

You can use read replicas in multi- regions & use you it for a ___________ in case of region issue & local performance improve, less latency but also has a replication cost

Answer 27

Disaster recovery

Question 28

____________ is used to get managed Redis or Memcached databses

Answer 28

Elasticache

Question 29

_________ databases are caches that are in-memory databases with high performance & low latency

Answer 29

Redis or Memcached

Question 30

Whenever you see "in-memory" database should think of ___________

Answer 30

elastichache

Question 31

________________ helps reduce load off databases for read-intensive workloads

Answer 31

Elasticache

Question 32

____________ is fully managed and highly available with replication across 3 AZ

Answer 32

DynamoDB

Question 33

DynamoDB is a __________ database

Answer 33

NoSQL database (not a relational database)

Question 34

___________ has a single-digit millisecond latency- low latency retrieval & it scales to massive workloads, distributed "serverless" database

Answer 34

DynamoDB

Question 35

DynamoDB is a __________ database

Answer 35

Key/value

Question 36

_______________ is a fully managed in-memory cache for dynamoDB (will give you a 10x performance improvement)

Answer 36

DynamoDB accelerator-DAX

Question 37

What is the difference between elasicache & dynamoDB DAX?

Answer 37

DAX is only used for & is integrated with dynamnoDB, while elasticache can be used for other databases

Question 38

_______________ make dynamoDB tables accessible with low latency in multiple- regions

Answer 38

DynamoDB global tables

Question 39

With dynamoDB-global tables its an ___________ replication (read/write to any AWS region)

Answer 39

Active-Active

Question 40

______________ is based on PostgreSQL but its not used for OLTP

Answer 40

Redshift

Question 41

Redshift uses ___________

Answer 41

OLAP Online analytical processing which is used to do analytics & data warehousing

Question 42

Redshift stores data in a __________ storage

Answer 42

Columnar (instead of row-based)

Question 43

Redshift __________ is a feature in redshift that allows you to automatically provision & scale data warehouse underlying capacity

Answer 43

Redshift serverless

Question 44

With ________________ you run analytics workloads without managing data warehouse infrastructure

Answer 44

Redshift serverless

Question 45

What does EMR mean?

Answer 45

Elastic Mapreduce

Question 46

________ helps create Hadoop clusters (big data) to analyze & process vast amount of data

Answer 46

EMR

Question 47

In Hadoop the cluster can be made of hundreds of ______________

Answer 47

EC2 instances

Question 48

What are the different use cases for EMR?

Answer 48

- Data processing - Machine learning - Web indexing - Big data

Question 49

__________ is a serverless query service to perform analytics against S3 objects

Answer 49

Amazon athena

Question 50

Amazon Athena uses __________ language to query files

Answer 50

SQL

Question 51

___________ analyze data in S3 using serverless SQL

Answer 51

Amazon athena

Question 52

_____________ is a serverless machine learning-powered business intelligence service to create interactive dashboard

Answer 52

Amazon quicksight

Question 53

___________ is the same for MongoDB (which is a NoSQL database)

Answer 53

DocumentDB

Question 54

________________ is a fully managed graph database

Answer 54

Amazon Neptune

Question 55

A popular graph datasets would be a ____________

Answer 55

Social network

Question 56

What does QLDB mean?

Answer 56

Stands for quantum ledger database

Question 57

A _________ is a book recording financial transactions

Answer 57

ledger

Question 58

_____________ is used to just record financial transaction in AWS

Answer 58

Amazon QLDB

Question 59

Amazon QLDB is used to review history of all the changes made to your application data over time & its an _________ system which means no entry can be removed or modified, cryptographically verifiable

Answer 59

Immutable

Question 60

What is the difference with amazon managed blocked chain and Amazon QLDB?

Answer 60

With Amazon QLDB there is no concept of decentralization, which means there's just a central database owened by amazon but with managed blockchain, its gonna have a decentralized component

Question 61

_______________ makes it possible to build applications where multiple parties can execute transaction without the need for a trusted, central authority

Answer 61

Amazon managed blockchain

Question 62

Amazon managed blockchain is compatible with the frameworks ___________ & __________

Answer 62

Hyperledger fabric & ethereum

Question 63

___________ is a managed extract, transform & load (ETL) service

Answer 63

AWS Glue

Question 64

With __________ you get quick & securely migrated databases to AWS, resilient, self-healing (used to migrate databases)

Answer 64

DMS (Database migration service)

Question 65

___________ is a fully managed, petabyte-scale data warehouse service in the cloud.

Answer 65

Amazon Redshift

Question 66

__________ is an interactive query service that makes it easy to analyze data in Amazon S3 using standard SOL. Athena is serverless, so there is no infrastructure to manage, and you pay only for the queries that you run.

Answer 66

Amazon Athena

Question 67

________ is a fully managed extract, transform, and load (ETL) service that makes it easy for customers to prepare and load their data for analytics.

Answer 67

AWS Glue

Question 68

_____________ helps you migrate databases to AWS quickly and securely. The source database remains fully operational during the migration, minimizing downtime to applications that rely on the database.

Answer 68

AWS Database Migration Service

Question 69

The ____________ is a central repository to store structural and operational metadata for all your data assets. For a given data set, you can store its table definition, physical location, add business relevant attributes, as well as track how this data has changed over time.

Answer 69

AWS Glue Data Catalog

Question 70

____________ is a SOL managed service that makes it easy to set up, operate, and scale a relational database in the cloud. It is suited for OLTP workloads

Answer 70

Amazon Relational Database Service (Amazon RDS)