Databases Flashcards
TRUE or FALSE: Patching or RDS OS and DB is Amazon’s responsibility
TRUE
Maximum RDS Storage Size
16TB
Is RDS serverless?
FALSE
My RDS is not attaching to my EC2 unit what might be the issue?
Make sure to add EC2 security group to rds security group
TRUE or FALSE: A restored RDS database has the same RDS endpoint
FALSE
Prerequisite for enabling Read Replica on RDS Database
Must have automatic backups turned on
TRUE or FALSE: You can have a RDS Read Replica in a different region
TRUE
What RDS are available (6)?
SQLServer
Oracle
MySQLServer
PostgreSQL
Aurora
MariaDB
What types of backups does RDS offer?
1) Automated Backups
2) DB Snapshot
What is the Retention Period of an RDS Automated Backup?
1-35 days
Describe an RDS Automated Backup
Takes a full daily snapshot and store logs throughout the day.
Recovery AWS chooses most recent daily backup and applies logs
Recovery is down to second w/ in retention period (Point int time recovery)
Default
Backups stored on s3 (free storage equal to size of DB)
Storage I/O may be suspended and may experience elevated latency during backup
Can you encrypt an RDS database?
Yes, encryption is done at rest using KMS.
But you cannot encrypt a currently existing DB
How to encrypt an existing DB?
Have to create a snapshot and encrypt that
What is Multi-AZ?
Host RDS in multiple availability zones for DISASTER RECOVERY.
Note this does nothing for performance.
What is Read Replica?
It is a way to scale out a DB load over multiple read replicas. Uses async replication from primary RDS to read replicas.
Use this on heavy read DB workloads.
Used for SCALING
Must have AUTO BACKUPS on in order to deploy read replica.
How many read replicas can you have?
5
Can you promote RR to become own DB?
Yes, but note this breaks replication
Which RDS Databases have RR capabilities?
MySQL
PostgreSQL
MariaDB
Aurora
How to collect all SQL statements that take a long time to execute?
Enable slow query log in RDS
Default READ consistency of Dynamo DB
Eventually Consistent Reads
but can get strong consistent
How to add Caching to DynamoDB to increase preformance
DAX
of AZ for DynamoDB
At least 3
What type of storage is DynamoDB stored on
SSD
IF you need ACID all or nothing on DynamoDB
Transactions
TRUE or FALSE DynamoDB On Demand Backup and Restore effects table preformance
FALSe
TRUE or FALSE DynamoDB Point in time recovery is enabled by default
FALSE
DynamoDB PITR max # of days to restore from
35 days
DynamoDB PITR latest retore time
5 minutes
TRUE or FALSE DynamoDB tables can be replicated across Regions
TRUE, DynamoDB Global Tables (based on DynamoDB streams)
Benefits of DynamoDB global tables
Multi-region redundandy
Disaster Recovery
High Availability
Want to move MongoDB to the Cloud
Use AWS Database Migration Service
Select AWS DocumentDB
Database used for big database workloads distributed over many servers (NoSQL)
Cassandra
What is AWS Keyspaces
Allows you to run your Cassandra DB in AWS
Serverless
What AWS Service is used for Graph DB ?
Neptune
AWS Service with NoSQL immutable database (Ledger database)
QLDB
Uses for QLDB
Crypto
Bank Transactions
Shipping
Claims System
System of Record Application
AWS Time Series Database
Amazon Timestream
Examples of time series data
IoT
Analytics
Devops Applications
Need a database that is relational and can store petabytes of data
Redshift
Max size of Redshift database
16 PB of data
Automatically on-demand scaling database which is a budget friendly service based on Aurora
Aurora Serverless
ACU units are about how big?
Aurora Compute Units are approx
2 GiB memory , matching CPU, and netoworking
Aurora allows for how many copies of data (data resilency)
6 copies of data across 3 AZ
How to implement high availability on Aurora
Enable multi-AZ
6 popular use cases for aurora serverless
Variable Workloads
Multi-Tenant Apps
New Apps
Dev & Test apps
Multi-Use Apps
Capacity planning
How to manage capacity planning on Aurora Serverless databases?
Set Min and Max ACU you want to use
Then you are billed per second for what you actually use
