You are viewing a free preview of this lesson.
Subscribe to unlock all 10 lessons in this course and every other course on LearningBro.
Microsoft Azure provides a comprehensive portfolio of managed database services, spanning relational, NoSQL, in-memory, and graph workloads. Understanding which service to choose — and when — is essential for building cost-effective, scalable, and resilient data architectures in the cloud.
Before cloud, organisations purchased servers, installed database software, configured replication, scheduled backups, and managed patches. This consumed significant time and budget. Azure's managed database services shift that operational burden to Microsoft:
| Responsibility | Self-Managed | Azure Managed |
|---|---|---|
| Hardware provisioning | You | Azure |
| OS patching | You | Azure |
| Database engine patching | You | Azure |
| Backups | You | Azure (automated) |
| High availability | You | Azure (built-in) |
| Scaling | You | Azure (elastic) |
| Monitoring | You (install agents) | Azure Monitor (built-in) |
| Security patches | You | Azure |
With managed services you focus on schema design, query optimisation, and application logic rather than infrastructure.
Azure SQL Database is a fully managed platform-as-a-service (PaaS) built on the Microsoft SQL Server engine. It is the most widely adopted Azure database service for new cloud-native applications.
Azure SQL Database supports T-SQL, stored procedures, views, triggers, and most SQL Server features. It provides automatic backups, point-in-time restore, and built-in high availability with a 99.99% SLA.
SQL Managed Instance provides near-100% compatibility with the on-premises SQL Server engine. It is designed for lift-and-shift migrations that require features such as SQL Server Agent, cross-database queries, CLR integration, linked servers, and Service Broker.
Managed Instance deploys into a virtual network, giving you full control over network isolation — unlike Azure SQL Database, which uses firewall rules and private endpoints.
For workloads that need full control over the SQL Server instance — such as specific OS-level configurations, third-party software, or legacy features — you can run SQL Server on Azure Virtual Machines. Microsoft provides pre-configured VM images with SQL Server pre-installed. You manage the OS and database engine, but Azure handles the underlying hardware.
A fully managed PostgreSQL service available in two deployment modes:
Supports PostgreSQL extensions such as PostGIS, pg_stat_statements, and pgvector for AI workloads.
A fully managed MySQL service, also available in Flexible Server and Single Server modes. It supports MySQL 5.7 and 8.0, read replicas, and automatic backups. Commonly used for web applications, content management systems, and e-commerce platforms.
A managed MariaDB service. Note that Microsoft has announced the retirement path for this service, recommending migration to Azure Database for MySQL Flexible Server.
Azure Cosmos DB is a globally distributed, multi-model database designed for mission-critical applications requiring single-digit millisecond latency and 99.999% availability.
Cosmos DB supports multiple APIs:
| API | Data Model |
|---|---|
| NoSQL (native) | JSON documents |
| MongoDB | BSON documents |
| PostgreSQL (distributed) | Relational (Citus-based) |
| Cassandra | Wide-column |
| Gremlin | Graph |
| Table | Key-value |
Throughput is measured in Request Units (RUs), and data is automatically partitioned and replicated across regions.
A simple NoSQL key-value store within Azure Storage accounts. It stores semi-structured data using PartitionKey and RowKey pairs. Table Storage is inexpensive for large volumes of data that do not require complex queries. For more advanced NoSQL needs, Cosmos DB (Table API) is recommended.
Azure Cache for Redis provides a fully managed Redis instance for caching, session management, real-time analytics, and message brokering. It supports Redis data structures (strings, hashes, lists, sets, sorted sets, streams) and features such as Redis clustering, geo-replication, and data persistence.
Tiers range from Basic (development) through Standard and Premium to Enterprise (Redis Enterprise with RediSearch, RedisJSON, and RedisTimeSeries modules).
DMS is a fully managed service for migrating databases to Azure with minimal downtime. It supports:
DMS supports both offline (one-time) and online (continuous sync) migration modes. Online migrations keep the source database operational during migration, cutting over when you are ready.
| Requirement | Recommended Service |
|---|---|
| Cloud-native relational app (SQL Server) | Azure SQL Database |
| Lift-and-shift SQL Server migration | Azure SQL Managed Instance |
| Full SQL Server control, specific OS needs | SQL Server on Azure VMs |
| Open-source PostgreSQL | Azure Database for PostgreSQL Flexible Server |
| Open-source MySQL | Azure Database for MySQL Flexible Server |
| Globally distributed, low-latency NoSQL | Azure Cosmos DB |
| Simple key-value storage | Azure Table Storage |
| In-memory caching and sessions | Azure Cache for Redis |
| Database migration to Azure | Azure Database Migration Service |
When choosing a database service, consider:
Many modern applications use multiple database services together:
Web Application
|
|-- Azure SQL Database (transactional data: orders, users)
|-- Azure Cosmos DB (product catalogue: global, low-latency reads)
|-- Azure Cache for Redis (session cache, shopping cart)
|-- Azure Table Storage (audit logs, telemetry)
Each database is chosen for its strengths, rather than forcing all data into a single engine.
Separate write and read models using different databases:
Writes → Azure SQL Database (normalised, ACID)
|
|-- Change feed / event
|
Reads → Azure Cosmos DB (denormalised, fast reads)
Azure offers a rich set of managed database services covering relational, NoSQL, in-memory, and migration workloads. Azure SQL Database and SQL Managed Instance serve SQL Server workloads. Azure Database for PostgreSQL and MySQL support open-source engines. Cosmos DB provides globally distributed NoSQL with multiple APIs. Azure Cache for Redis delivers in-memory performance. The Azure Database Migration Service helps you move existing databases to Azure with minimal downtime. In the next lesson, we will take a deep dive into Azure SQL Database.