Databases & Analytics

Databases \& Analytics

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
Managed Databases: AWS takes care of maintenance, backups, and security for databases.
Benefits: Reduced operational complexity, built-in high availability, disaster recovery, scalability, and enhanced security.
Types:
- Relational Databases (SQL)
- NoSQL Databases
- Data Warehousing
- In-memory Caching

Relational Databases (SQL)

Structured Data: Stored in predefined schema tables, managed with SQL.
Use Cases: Transactional applications, financial systems.
Examples: MySQL, PostgreSQL, Oracle, SQL Server, MariaDB.

NoSQL Databases

Flexible Schema: No predefined schema, designed for fast and scalable data storage.
Use Cases: Real-time applications, IoT, mobile apps.
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: DynamoDB, MongoDB (DocumentDB), Key-value, document, graph, in-memory, search databases

NoSQL data example: JSON

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…

{
  "name": "Abc",
  "age": 30,
  "cars": [
    "Ford",
    "BMW",
    "Fiat"
  ],
  "address": {
    "type": "house",
    "number": 23,
    "street": "Abc Road"
  }
}

Databases & Shared Responsibility on AWS

AWS Responsibility	Customer Responsibility
Infrastructure management, backups, patches	Data security, encryption, access controls (IAM)
Availability and failover	Data management, monitoring, performance tuning

AWS RDS Overview

RDS (Relational Database Service): Fully managed service for relational databases.
- It’s a managed DB service for DB use SQL as a query language.
- Supports MySQL, PostgreSQL, MariaDB, Oracle, SQL Server.
- Handles backup, patching, high availability (Multi-AZ), and scaling.

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 can’t SSH into your instances

RDS Deployments

Read Replicas: Improves read performance, asynchronous replication.
Multi-AZ: Automatic failover, high availability for production environments.
Multi-Region: Disaster recovery across regions, global availability.

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

RDS Deployments: Multi-Region

Multi-Region (Read Replicas)
- Disaster recovery in case of region issue
- Local performance for global reads
- Replication cost

Multi-Region

Amazon Aurora

Amazon Aurora: High-performance RDS database.
- Compatible with MySQL and PostgreSQL.
- 5x faster than MySQL, 3x faster than PostgreSQL.
- Auto-scaling storage up to 64 TB.
- Supports Multi-AZ and up to 15 read replicas.
- Great for enterprise-grade applications requiring high availability and performance.
- Aurora costs more than RDS (20% more) – but is more efficient

Amazon ElastiCache Overview

ElastiCache: In-memory data caching service.
- Redis: Advanced key-value store with replication and persistence.
- Memcached: Simple, memory-only caching service.
- Reduces database load and speeds up applications by caching frequent queries.
- Caches are in-memory databases with high performance, low latency
- AWS takes care of OS maintenance / patching, optimizations, setup, configuration, monitoring, failure recovery and backup

DynamoDB

Fully managed, serverless NoSQL database.
Supports key-value and document data models.
Automatically scales based on demand.
Provides high availability and durability with replication across 3 AZ
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)

In-memory caching for DynamoDB.
10x faster read performance. Single-digit millisecond latency to microseconds latency – when accessing your DynamoDB tables
Secure, highly scalable & highly available
Ideal for use cases where low-latency reads are critical.

DynamoDB Global Tables

Multi-region replication for global applications.
Low-latency reads and writes across multiple regions.
Ensures data availability globally with multi-master replication.

Redshift Overview

Managed data warehousing service.
Optimized for online analytical processing (OLAP) and big data analytics.
Uses columnar storage for fast query performance.
10x better performance than other data warehouses, scale to PBs of data
Columnar storage of data (instead of row based)
Supports integration with BI tools (QuickSight, Tableau).
Massively Parallel Query Execution (MPP), highly available.
Has a SQL interface for performing the queries.
Pay-per-query or reserved instances for cost savings.
Designed for massive datasets.

Amazon EMR (Elastic MapReduce)

Managed big data processing service.
Uses Hadoop, Apache Spark, and Hive for processing large data sets.
Ideal for data transformation, machine learning, and ETL (Extract, Transform, Load).
Integration with S3, DynamoDB, and Redshift.
The clusters can be made of hundreds of EC2 instances
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
Use SQL to query structured and unstructured data stored in S3.
No infrastructure to manage, pay-per-query.
Supports various formats like CSV, JSON, Parquet, and ORC.
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

Business Intelligence (BI) tool for data visualization.
Serverless machine learning-powered business intelligence service to create interactive dashboards
Fast, automatically scalable, embeddable, with per-session pricing
Supports data from S3, Redshift, RDS, and other AWS data sources.
Pay-per-session pricing model for cost efficiency.
Use cases:
- Business analytics
- Building visualizations
- Perform ad-hoc analysis
- Get business insights using data

DocumentDB (with MongoDB Compatibility)

Managed document database, MongoDB-compatible.
DocumentDB is the same for MongoDB (which is a NoSQL database)
Highly scalable and durable with Multi-AZ.
Built for JSON document storage.
Aurora storage automatically grows in increments of 10GB, up to 64 TB.
Automatically scales to workloads with millions of requests per seconds
Use cases: Content management, cataloging, and mobile backends.

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

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

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