Roadmap › Azure Databases — Azure SQL, Managed Instance, Cosmos DB, PostgreSQL and Migration › Module: Azure SQL
Lessons in this course (9)
1. Azure SQL Database, Managed Instance and SQL on VM — choosing
Basic★ Must knowLesson 1 of 9
| Azure SQL Database | SQL Managed Instance | SQL Server on Azure VM | |
|---|---|---|---|
| Model | PaaS database | PaaS instance | IaaS |
| Compatibility | Database-scoped features | Near-full instance features (SQL Agent, cross-DB queries, CLR, DB Mail, linked servers) | 100 % |
| Patching, backups, HA | Automatic | Automatic | You (with helpers like SQL IaaS Agent extension) |
| Networking | Public endpoint + firewall or private endpoint | Inside your VNet | Your VNet |
| Max size | Up to 4 TB (GP/BC), 128 TB Hyperscale | Up to 16 TB (instance storage) | Disk limits |
| Typical use | New apps, SaaS (database per tenant), microservices | Migrating many existing databases with minimal change | Legacy apps, SSRS/SSIS on the same server, special configs |
A logical server (myserver.database.windows.net) is just a management/connection endpoint holding logins, firewall rules and Entra admin — databases on it are independent.