# Summary

• Relational Databases - OLTP: RDS & Aurora (SQL)&#x20;

• Differences between Multi-AZ, Read Replicas, Multi-Region&#x20;

• In-memory Database: ElastiCache&#x20;

• Key/Value Database: DynamoDB (serverless) & DAX (cache for DynamoDB)&#x20;

• Warehouse - OLAP: Redshift (SQL)&#x20;

• Hadoop Cluster: EMR&#x20;

• Athena: query data on Amazon S3 (serverless & SQL)&#x20;

• QuickSight: dashboards on your data (serverless)&#x20;

• DocumentDB: “AuroraforMongoDB” (JSON–NoSQL database)&#x20;

• AmazonQLDB: Financial Transactions Ledger (immutable journal, cryptographically verifiable)&#x20;

• Amazon Managed Blockchain: managed Hyperledger Fabric & Ethereum blockchains&#x20;

• Glue: Managed ETL (Extract Transform Load) and Data Catalog service&#x20;

• Database Migration: DMS&#x20;

• Neptune: graph database
