Database - How to choose?

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Database FamilyWhen Would You Use It?Use CaseOptimized ForAWS Related Database Engines or Services3rd-party
RelationalMigrating on-premises relational workloads, ad hoc query patternsTraditional applications, enterprise resource planning (ERP), customer relationship management (CRM), e-commerceStructured data in tables, rows, and columns, supports complex ad hoc queries through joinsAmazon Aurora, Amazon RDSMySQL, Postgres
Amazon RedshiftGoogle BigQuery
Key-valueSession stores, shopping carts, scalable for high volumes of state changesHigh-traffic web applications, e-commerce systems, gaming applicationsFast access to large amounts of structured, semi-structured, or unstructured data with high read and write throughputAmazon DynamoDBGoogle Bigtable
DocumentStoring JSON documents with rich querying abilitiesContent management, catalogs, user profilesStoring semi-structured data as JSON documentsAmazon DocumentDB (with MongoDB compatibility)MongoDB
In-memoryImproving read performance through cachingCaching, session management, gaming leaderboards, geospatial applicationsApplications requiring sub-millisecond data accessAmazon ElastiCache, Amazon MemoryDB for RedisRedis
Wide columnMigrating on-premises Cassandra workloads, high-speed data processingHigh-scale industrial apps for equipment maintenance, fleet management, and route optimizationWorkloads requiring heavy reads/writes, high throughput, low latency, and linear scalabilityAmazon KeyspacesApache Cassandra
GraphFraud detection, recommendation engines, airline networksFraud detection, social networking, recommendation enginesStoring and navigating relationshipsAmazon Neptuneneo4j
Time seriesManaging large amounts of time series data from various sourcesInternet of Things (IoT) applications, DevOps, industrial telemetryStoring and querying data that changes over timeAmazon Timestream
LedgerCommunicating with other entities, maintaining verifiable history of database changesSystems of record, supply chain, registrations, banking transactionsMaintaining a complete and verifiable history of database changesAmazon Quantum Ledger Database (QLDB)

Structured, semi-structured, and unstructured data

Structured dataSemi-structured dataUnstructured data
Data pie10 to 15 %5% to 10%80% to 90%
ExampleRDS table, spreadsheetHTML, JSON, XMLMultimedia (photo, audio, video), text document, scanned PDF

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