> For the complete documentation index, see [llms.txt](https://chxmxii.gitbook.io/aws-ccp/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://chxmxii.gitbook.io/aws-ccp/databases-and-analytics/databases-and-analytics.md). # Databases & Analytics Lets learn about the different types of databases in the cloud. ## RDS Deployments : Read Replicas, Multi-AZ, Multi-Region : #### Read Replicas : * Scale the read workload of your DB * Can Create up to 5 Read Replicas * Data is only written to the main DB \=> Is like creating a symbolic link to the main DB. #### Multi-AZ : * Failover in case of AZ outage (high availability) * Data is only read/written to the main database * Can only have 1 other AZ as failover \=> Is like creating a hard link so when something or in case of issues with main DB. #### Multi-Region ( Read Replicas) : * Disaster recovery in case of region issue. * Local performance for global reads * Replication cost. \=> Something like fault-tolerant. ## Databases : #### RDS - Relational Database Service : * SQL relational database service. * It allows you to create databases in the cloud that are managed by AWS : Aurora, MySQL, MariaDB, Oracle, Microsoft SQL Server, Aurora (AWS prop database) => Compatible database * Simplifies management, e.g. manages backups software patching, automatic failure detection and recovery, etc. #### Aurora : * Proprietary technology by AWS. * Relational database engine that is fully managed built for the cloud. * MySQL and PostgreSQL compatible database. * 5x faster than MySQL and 3x faster than PostgreSQL. This performance is on par with commercial databases, at 1/10th the cost. * Fault-tolerant and self-healing * AWS manages hardware provisioning, software patching, setup, configuration or backups etc... #### ElastiCache : * In-memory database with very high performance and low latency. * Compatible with **Redis** or **Memcached** engines. * For example, if you're regularly reading an intensive database, it could be helpful to reduce the load with ElastiCache * AWS takes care of OS maintenance / patching, optimizations, setup, configuration, monitoring, failure recover and backups #### DynamoDB : * A fully managed, NoSQL key/value database service. * Offers encryption for the data. * Can scale to massive workloads seamlessly. distributed Serverless (no servers to manage or maintain) databse. * Single-digit \ Very low latency and very high performance. * Low cost and auto-scaling capabilities. * Integrated with IAM for security, authorization and administration * It is NON-RELATIONAL! #### DynamoDB Accelerator - DAX : * Fully Managed in-memory cache for DynamoDB * 10x Performance improvement * 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. #### DocumentDB : * Fully managed, NoSQL Document Database * MongoDB compatible * Different to DynamoDB as that was a key/value database and this is a documentDB * MongoDB is used to store, query and index JSON data * Similar " deployment concepts" as Aurora * Fully Managed, highly available which 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. #### Redshift : * Fully managed, PETABYTE-scale data warehousing service. * it's an OLAP (Online Analytical Processing) database. * Uses columnar storage, instead of row based. * Pay as you go based on the instance provisioned. * Has a SQL interface per performing the queries * BI tools such as AS Quicksight or tableau integrate with it. #### Neptune : * Fully managed graph database * Highly available across 3 AZ, with up to 15 read replicas * can store up to billions of relations and query the graph with milliseconds latency * Fast, reliable, fully managed graph data base service * Great for knowledge graphs "Wikipedia", fraud detection. #### Amazon QLDB - Quantum Ledger Database : * A ledger is a book recording financial transactions * Fully managed, serverless, high available, Replication across 3AZ * 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 #### Amazon Managed Blockchain : * Blockchain makes it possible to build applications where multiple parties can execute transactions without the need for a trusted central authority * AMB is a managed service to join public blockchain networks or create your own scalable private network * Compatible with the frameworks Hyperledger Fabric & Ethereum ## Analytics : #### Amazon EMR - Elastic MapReduce : * Helps create Hadoop clusters for data processing, machine learning, big data, etc.. * Run and scale Apache Spark, Hive, Presto, and other big data frameworks * Basically it helps analyze data using Hadoop Clusters * Auto-scaling and integrated with spot instances. #### 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 * Data integrated with RDS, Aurora, Athena, Redshift, S3.. #### Athena : * Serverless service used to query data in S3 using SQL. * Pay per query (only pay for data scanned). * Secured through IAM * Use Cases : one-time SQL queries, Serverless queries on s3, log analytics. #### Amazon 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. #### 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 ## 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 Databse ->** DynamoDB "Serverless" & DAX (Cache for dynamoDB) * **Warehouse - OLAP** (Online Analytics Processing) -> Redshift "SQL" * **Hadoop Cluster ->** EMR - Elastic MapReduce * **Athena ->** Query Data on Amazon S3 "Serverless & SQL" * **QuickSight ->** Dashboards on your data "Serverless" * **DocumentDB ->** " Aurora for MongoDB" (JSON - NoSQL database). * **Amazon QLDB (Quantum Ledger DB) ->** 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 - Database Migration Service. Support homogenous and heterogenous migration. * **Neptune ->** Graph Database.