Migration process overview
Choosing IaaS or PaaS
SQL Server on Azure VMs: A SQL Server instance installed and hosted on a Windows Virtual Machine running in Azure, also known as Infrastructure as a Service (IaaS).
Azure SQL Database: A fully managed SQL database Azure service, also known as Platform as a Service (PaaS).
Choose SQL Server in Azure VMs if:
Choose Azure SQL Database if:
Differences between each service based on a set of scenarios:
|Scenario||SQL Server in Azure VMs||Azure SQL Database|
|Migration||Requires minimal changes to your database.||May require changes to your database if you use features unavailable in Azure SQL, as determined by the Data Migration Assistant, or if you have other dependencies such as locally installed executables.|
|Managing availability, recovery, and upgrades||Availability and recovery are configured manually. Upgrades can be automated with VM Scale Sets.||Automatically managed for you.|
|Underlying OS configuration||Manual configuration.||Automatically managed for you.|
|Managing database size||Supports up to 256 TB of storage per SQL Server instance.||Supports 8 TB of storage before needing a horizontal partition.|
|Managing costs||You must manage SQL Server license costs, Windows Server license costs, and VM costs (based on cores, RAM, and storage).||You must manage service costs (based on eDTUs or DTUs, storage, and number of databases if using an elastic pool). You must also manage the cost of any SLA.|