Files
AWS-CCP-Notes/sections/databases.md
2022-08-15 18:24:12 +09:00

264 lines
10 KiB
Markdown
Raw Blame History

This file contains ambiguous Unicode characters
This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.
# Databases
## Databases Intro
* Storing data on disk (EFS, EBS, EC2 Instance Store, S3) can have its limits
* Sometimes, you want to store data in a database…
* You can structure the data
* You build indexes to efficiently query / search through the data
* You define relationships between your datasets
* Databases are optimized for a purpose and come with different features, shapes and constraint
## Relational Databases
* Looks just like Excel spreadsheets, with links between them!
* Can use the SQL language to perform queries / lookups
## NoSQL Databases
* NoSQL = non-SQL = non relational databases
* NoSQL databases are purpose built for specific data models and have flexible schemas for building modern applications.
* Benefits:
* Flexibility: 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 the data model
* Examples: Key-value, document, graph, in-memory, search databases
### NoSQL data example: JSON
* JSON = JavaScript Object Notation
* JSON is a common form of data that fits into a NoSQL model
* Data can be nested
* Fields can change over time
* Support for new types: arrays, etc…
```json
{
"name": "John",
"age": 30,
"cars": [
"Ford",
"BMW",
"Fiat"
],
"address": {
"type": "house",
"number": 23,
"street": "Dream Road"
}
}
```
## Databases & Shared Responsibility on AWS
* AWS offers use to manage different databases
* Benefits include:
* Quick Provisioning, High Availability, Vertical and Horizontal Scaling
* Automated Backup & Restore, Operations, Upgrades
* Operating System Patching is handled by AWS
* Monitoring, alerting
* Note: many databases technologies could be run on EC2, but you must handle yourself the resiliency, backup, patching, high availability, fault tolerance, scaling
## AWS RDS Overview
* RDS stands for Relational Database Service
* Its a managed DB service for DB use SQL as a query language.
* It allows you to create databases in the cloud that are managed by AWS
* Postgres
* MySQL
* MariaDB
* Oracle
* Microsoft SQL Server
* **Aurora (AWS Proprietary database)**
### Advantage over using RDS versus deploying DB on EC2
* RDS is a managed service:
* Automated provisioning, OS patching
* Continuous backups and restore to specific timestamp (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 and horizontal)
* Storage backed by EBS (gp2 or io1)
* BUT you cant SSH into your instances
## Amazon Aurora
* Aurora is a proprietary technology from AWS (not open sourced)
* PostgreSQL and MySQL are both supported as Aurora DB
* Aurora is “AWS cloud optimized” and claims 5x performance improvement over MySQL on RDS, over 3x the performance of Postgres on RDS
* Aurora storage automatically grows in increments of 10GB, up to 64 TB.
* Aurora costs more than RDS (20% more) but is more efficient
* Not in the free tier
## RDS Deployments: Read Replicas, Multi-AZ
Read Replicas | Multi-AZ
---- | ----
Scale the read workload of your DB | Failover in case of AZ outage (high availability)
Can create up to 5 Read Replicas | Data is only read/written to the main database
Data is only written to the main DB | Can only have 1 other AZ as failover
![Read Replicas | Multi-AZ](/images/read_replicas_multi_AZ.png)
## RDS Deployments: Multi-Region
* Multi-Region (Read Replicas)
* Disaster recovery in case of region issue
* Local performance for global reads
* Replication cost
![Multi-Region](/images/multi_region.png)
## Amazon ElastiCache Overview
* The same way RDS is to get managed Relational Databases…
* ElastiCache is to get managed Redis or Memcached
* Caches are in-memory databases with high performance, low latency
* Helps reduce load off databases for read intensive workloads
* AWS takes care of OS maintenance / patching, optimizations, setup, configuration, monitoring, failure recovery and backup
## DynamoDB
* Fully Managed Highly available with replication across 3 AZ
* NoSQL database - not a relational database
* Scales to massive workloads, distributed “serverless” database
* Millions of requests per seconds, trillions of row, 100s of TB of storage
* Fast and consistent in performance
* Single-digit millisecond latency low latency retrieval
* Integrated with IAM for security, authorization and administration
* Low cost and auto scaling capabilities
* Standard & Infrequent Access (IA) Table Class
### DynamoDB Accelerator - DAX
* Fully Managed in-memory cache for DynamoDB
* 10x performance improvement single- digit millisecond latency to microseconds latency when accessing your DynamoDB tables
* Secure, highly scalable & highly available
* Difference with ElastiCache at the CCP level: DAX is only used for and is integrated with DynamoDB, while ElastiCache can be used for other databases
### DynamoDB Global Tables
* Make a DynamoDB table accessible with low latency in multiple-regions
* Active-Active replication (read/write to any AWS Region)
## Redshift Overview
* Redshift is based on PostgreSQL, but its not used for OLTP (Online Transactional Processing)
* Its OLAP online analytical processing (analytics and data warehousing)
* Load data once every hour, not every second
* 10x better performance than other data warehouses, scale to PBs of data
* Columnar storage of data (instead of row based)
* Massively Parallel Query Execution (MPP), highly available
* Pay as you go based on the instances provisioned
* Has a SQL interface for performing the queries
* BI tools such as AWS Quicksight or Tableau integrate with it
## Amazon EMR
* EMR stands for “Elastic MapReduce”
* EMR helps creating Hadoop clusters (Big Data) to analyze and process vast amount of data
* The clusters can be made of hundreds of EC2 instances
* Also supports Apache Spark, HBase, Presto, Flink
* EMR takes care of all the provisioning and configuration
* Auto-scaling and integrated with Spot instances
* Use cases: data processing, machine learning, web indexing, big data
## Amazon Athena
* Serverless query service to analyze data stored in Amazon S3
* Uses standard SQL language to query the files
* Supports CSV, JSON, ORC, Avro, and Parquet (built on Presto)
* Pricing: $5.00 per TB of data scanned
* Use compressed or columnar data for cost-savings (less scan)
* Use cases: Business intelligence / analytics / reporting, analyze & query VPC Flow Logs, ELB Logs, CloudTrail trails, etc...
* **analyze data in S3 using serverless SQL, use Athena**
## Amazon QuickSight
* Serverless machine learning-powered business intelligence service to create interactive dashboards
* Fast, automatically scalable, embeddable, with per-session pricing
* Use cases:
* Business analytics
* Building visualizations
* Perform ad-hoc analysis
* Get business insights using data
* Integrated with RDS, Aurora, Athena, Redshift, S3…
## DocumentDB
* Aurora is an “AWS-implementation” of PostgreSQL / MySQL …
* DocumentDB is the same for MongoDB (which is a NoSQL database)
* MongoDB is used to store, query, and index JSON data
* Similar “deployment concepts” as Aurora
* Fully Managed, highly available with replication across 3 AZ
* Aurora storage automatically grows in increments of 10GB, up to 64 TB.
* Automatically scales to workloads with millions of requests per seconds
## Amazon Neptune
* Fully managed graph database
* A popular graph dataset would be a social network
* Users have friends
* Posts have comments
* Comments have likes from users
* Users share and like posts…
* Highly available across 3 AZ, with up to 15 read replicas
* Build and run applications working with highly connected datasets optimized for these complex and hard queries
* Can store up to billions of relations and query the graph with milliseconds latency
* Highly available with replications across multiple AZs
* Great for knowledge graphs (Wikipedia), fraud detection, recommendation engines, social networking
## Amazon QLDB
* QLDB stands for ”Quantum Ledger Database”
* A ledger is a book **recording financial transactions**
* Fully Managed, Serverless, High available, Replication across 3 AZ
* Used to **review history of all the changes made to your application data** over time
* **Immutable** system: no entry can be removed or modified, cryptographically verifiable
* 2-3x better performance than common ledger blockchain frameworks, manipulate data using SQL
* Difference with Amazon Managed Blockchain: no decentralization component, in accordance with financial regulation rules
## Amazon Managed Blockchain
* Blockchain makes it possible to build applications where multiple parties can execute transactions without the need for a trusted, central authority.
* Amazon Managed Blockchain is a managed service to:
* Join public blockchain networks
* Or create your own scalable private network
* Compatible with the frameworks Hyperledger Fabric & Ethereum
## AWS Glue
* Managed extract, transform, and load (ETL) service
* Useful to prepare and transform data for analytics
* Fully serverless service
* Glue Data Catalog: catalog of datasets
* can be used by Athena, Redshift, EMR
## DMS Database Migration Service
* Quickly and securely migrate databases to AWS, resilient, self healing
* The source database remains available during the migration
* Supports:
* Homogeneous migrations: ex Oracle to Oracle
* Heterogeneous migrations: ex Microsoft SQL Server to Aurora
## Databases & Analytics Summary in AWS
* Relational Databases - OLTP: RDS & Aurora (SQL)
* Differences between Multi-AZ, Read Replicas, Multi-Region
* In-memory Database: ElastiCache
* Key/Value Database: DynamoDB (serverless) & DAX (cache for DynamoDB)
* Warehouse - OLAP: Redshift (SQL)
* Hadoop Cluster: EMR
* Athena: query data on Amazon S3 (serverless & SQL)
* QuickSight: dashboards on your data (serverless)
* DocumentDB: “Aurora for MongoDB” (JSON NoSQL database)
* Amazon QLDB: Financial Transactions Ledger (immutable journal, cryptographically verifiable)
* Amazon Managed Blockchain: managed Hyperledger Fabric & Ethereum blockchains
* Glue: Managed ETL (Extract Transform Load) and Data Catalog service
* Database Migration: DMS
* Neptune: graph database