SQL Server feature comparison for IaaS and PaaS

This is a part of a Series “Stairway to being an Azure SQL DBA“, in which I am planning to cover everything related to working as an Azure SQL DBA.

We saw in the previous blog there are multiple options of having a SQL Server in cloud. And also touched if any of the Azure SQL option effect the DBA activities or not.

The difference between Azure SQL Database, Managed Instance and IaaS environment is as below:

Azure SQL DatabaseManaged InstanceIaaS
Compatibility with On-Prem databasesSupports most on-prem database level capabilitiesSupports most of the on-prem Instance-level and database-level capabilittiesSupports everything that is there on-prem
BackupsAzure ManagedAzure ManagedYou need to manage 
Patching SQL ServerAzure ManagedAzure ManagedYou need to manage 
SQL Server VersionLatest stable Database EngineLatest stable Database EngineThe one you install
High AvailabilityCan be done from the Portal, fixed option availableCan be done from the Portal, fixed option availableAny HA can be configured, but has to be done manually
MigrationThis can be difficult as it has database and Instance level limitations, and lacks some features of a full-fledged SQL serverMigration in terms of compatibility is easy as many features available in On-Prem SQL Serve rare available here tooMigration is easy, as easy as taking backup and restoring it here.
CPU/MemoryIs configured separately for each and every databaseIs configured per instance levelSQL Server can use all the resources allocated to the VM
Connection for On-PremOn-Prem application can access data by whitelisting the app server IP in Azure SQL DatabaseNeed to configure VPN or Express RouteNeed to configure VPN or Express Route, can also be done by allocating a public IP to the VM and then whitelisting the On-prem server but the traffic is send over internet and so not secure enough.
CostRanges from $5 per month to $19k per month per databaseRanges from $800 to $43k per month per instanceDepends upon the VM size and SQL Server License
AdministrationDBA role is minimumDBA is required for managing the SQL ServerDBA works the same way as in on-prem environment
SLA99.99% SLA provided by MS99.99% SLA prvided by MS99.95% SLA provided but only for VM infrastructure, you are responsible for SQL Server uptime.

For the complete difference between Azure SQL Database and Managed Instance check the Power BI Report I have created Link

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s