When building cloud-native or hybrid applications on Azure, choosing the right database service is critical. Azure’s data platform spans relational and NoSQL offerings, delivering fully managed options, predictable performance, global distribution, and enterprise-grade security.
At a Glance Category Service Deployment Type Key Benefits Azure SQL Azure SQL Database PaaS Single DB, elastic pools, Hyperscale scaling Azure SQL Managed Instance PaaS Near 100% SQL Server compatibility SQL Server on Azure Virtual Machine IaaS Full OS/SQL control, custom extensions Open Source Relational Engines Azure Database for MySQL PaaS Community MySQL, high availability, scaling Azure Database for MariaDB PaaS Predictable performance, built-in security Azure Database for PostgreSQL PaaS Single & Flexible Server, HA, enterprise-grade Globally Distributed NoSQL (Multi-Model) Azure Cosmos DB PaaS JSON, MongoDB, Gremlin, Cassandra, Table APIs
Azure SQL Offerings Azure SQL delivers managed SQL Server–based engines with varying levels of control and compatibility:
Service Description Ideal Use Case Azure SQL Database Fully managed single databases, elastic pools, or Hyperscale for large-scale workloads. New cloud apps, SaaS, rapid scaling Azure SQL Managed Instance Hosted PaaS instance with near-100% compatibility to on-premises SQL Server. Lift-and-shift migrations, legacy apps SQL Server on Azure VM Infrastructure-level control over the OS and SQL Server instance. Custom extensions, unsupported PaaS features
Deployment and Scaling # Create a single Azure SQL Database az sql db create \ --resource-group myRG \ --server mySqlServer \ --name myDatabase \ --service-objective S0
Azure SQL Database Hyperscale supports up to 100 TB of storage and rapid auto-scaling—ideal for unpredictable workloads.
Azure Database for Open Source Relational Engines Azure’s managed services for MySQL, MariaDB, and PostgreSQL deliver community-driven engines with enterprise features:
Engine Deployment Model High Availability Scaling Options MySQL Single Server Zone redundant Vertical and read replicas MariaDB Single Server Zone redundant Vertical scaling PostgreSQL Single & Flexible Server Built-in HA Read replicas, burst
Quickstart: Deploy PostgreSQL Flexible Server az postgres flexible-server create \ --resource-group myRG \ --name myFlexServer \ --location eastus \ --tier Burstable \ --storage-size 128
Azure Cosmos DB Azure Cosmos DB is a fully managed, globally distributed NoSQL database service with multi-model support and five well-defined consistency levels:
Core (SQL) API for schemaless JSON.MongoDB API for wire-protocol compatibility.Gremlin API for graph data models.Cassandra API for wide-column workloads.Table API for key–value storage.
Global Distribution & Throughput { "location" : "East US" , "locations" : [ { "locationName" : "East US" , "failoverPriority" : 0 }, { "locationName" : "West Europe" , "failoverPriority" : 1 } ], "databaseThroughput" : 400 }
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