Databases Flashcards
What 6 relational databases are available with AWS RDS?
SQL server, PostregreSQL, Oracle, MariaDB, MySQL, Aurora
What does OLTP stand for?
Online transaction processing
What is OLTP?
OLTP is the processing of data from transactions in real time
What does OLAP stand for?
Online analytical processing
What is OLAP?
OLAP is the processing of complex queries to analyze historical data
What does Multi-AZ RDS do?
Creates an exact copy of production database in another AZ
What is a read replica?
a read-only copy of your database
Can read replicas be cross region?
Yes
Why don’t read replicas have its own DNS end point?
It does
Can read replicas be promoted to their own databases?
Yes
What specific setting is required for read replicas to be enabled?
Automatic backup
How many read replicas can you have per database?
5
What is Amazon Aurora?
a MySQL and PostgreSQL compatible relational database engine that combines the speed and agility of high end commercial databases with the simplicity and cost effectiveness of open source databases
How much space does Aurora start with?
10 GB
How many copies are of your data are guaranteed with Aurora? How is this composed?
6 copies. 2 copies in 3 AZ
Is the Aurora database self-healing?
Yes
In what platforms can you have replicas?
Aurora, MySQL, PostgreSQL
Are backups automated for Aurora?
Yes
How much do backups impact Aurora database performance?
Not at all
What is Aurora serverless?
An on-demand auto scaling configuration for the MySQL and PostgreSQL compatible editions of Aurora.
What are the benefits of Aurora Serverless DB Cluster?
An Aurora DB cluster automatically starts up, shuts down, and scales capacity up or down based on your applications needs
What are Aurora serverless use cases?
When you need a relatively simple, cost effective option for infrequent or unpredictable workloads
Can you share your Aurora snapshots with other accounts?
Yes
Are automated backups default for Aurora?
Yes
What is DynamoDB?
A fast and flexible NoSQL database service
What data models does DynamoDB support?
document and key-value data models
Is DynamoDB fully managed?
Yes
What are some examples where DynamoDB would be a great fit?
Mobile, web, gaming, ad-tech, IoT
What is the latency for DynamoDB?
Single digit millisecond
What storage service type does DynamoDB use?
SSD
Where is DynamoDB spread across?
3 geographically distinct data centers
Is strongly consistent reads or eventually consistent reads default?
eventually consistent
What is DAX?
DynamoDB Accelerator is a fully managed, highly available, in-memeory cache service for DynamoDB
By what factor does DAX improve DynamoDB?
10x
How is pricing structured for DynamoDB?
Pay per request
What is the encryption type at rest for DynamoDB?
KMS
What does ACID stand for?
ATOMIC, Consistent, isolated, durable
What does atomic in ACID mean?
All changes to data must be successful or no changes at all
What offering makes DynamoDB ACID?
DynamoDB transactions
What is DynamoDB Backups?
An on demand backup and restore service
What does DynamoDB Global Tables give you?
Manger multi master multi regional replication
What needs to be enabled for DynamoDB global tables?
DynamoDB streams
What is MongoDB?
A document database that allows for scalability and flexibility with your data as well as robust querying and indexing features
What is Amazon DocumentDB?
Allows you to run MongoDB on the AWS cloud. It’s a managed database service that scales with your workloads and safely and durably stores your database information
What is the advantage of AmazonDB over MongoDB?
Get rid of operational overheads like cluster management software, configuring backups, monitoring workloads
What is Cassandra?
A distributed database (ie it runs on many machines) that uses NoSQL
When is Cassandra typically used?
For big data solutions
What is Amazon keyspaces?
Amazons Apache Cassandra database service. Allows you to run Cassandra workloads on AWS.
What is the advantage of AWS keyspaces over Cassandra?
It is fully managed database. No need to worry about managing servers, software patching, etc.
Is Amazon keyspaces serverless?
Yes
What is Amazons graph database service?
Neptune
What is a ledger database?
It is a NoSQL database that is immutable, transparent, and has a cryptographically verifiable transaction log that is owned by one authority
What is Amazon Quantum Ledger Database?
QLDB is a fully managed ledger database that provides a transparent immutable and cryptographically verifiable transition log
What is Amazon timestream?
A fully managed database service for time series data
Is RDS suitable for OLAP or OLTP?
OLTP
What are read replicas meant to improve?
Scaling (improves read performance) not distasteful recovery
What is DynamoDB PITR?
Point in time recovery protects against accidental writes or deletes. Can restore any point in the last 35 days
What are the 4 ways you can scale an RDS in AWS?
Vertical scaling, scaling storage, creating read replicas, aurora serverless
What is the big thing you should be wary of when scaling storage?
it cant’t be scaled back down
