Summary

Azure SQL Database and SQL Managed Instance have different purchasing options and service tiers to support varying workloads. SQL Database has two purchase options, DTU and vCore, while SQL Managed Instance is only available with the vCore model. The DTU purchasing option measures performance in DTUs. A DTU hides the complexity of measuring performance in terms of CPU and memory and provides a simple way of measuring performance. It's good for teams that don't have specialized DBAs and for new databases/applications where we don't have historical performance metrics for the database.

The vCore model is more similar to an on-premises SQL Server wherein we get to choose compute (vCore) and storage separately. It's best for teams with specialized DBAs and for migrating on-premises workloads to Azure (where we have historical performance metrics for the database).

We also looked at different service tiers for each purchasing model and underlaying architecture model differences and use cases.

We learned how to use DMA to get SKU recommendations when migrating an on-premises SQL workload to SQL Database or SQL Managed Instance.

In the next chapter, we'll learn about techniques and considerations to migrate an on-premises SQL Server database to Azure SQL managed database offerings.