One of the challenges in moving to the cloud is achieving a similar level of performance to what you would get with dedicated hardware on-premises. The cloud is someone else's computer, and you are limited to the choices that the vendors allow you to rent. In many cases, you might even share the physical hardware resources with other customers, though many cloud providers have started to allow dedicated hardware reservations in the last few years.

One of the challenges of choosing a PaaS cloud database platform is that there are often restrictions that differ from a similar platform on-premises. This is often to ensure that one customer doesn't affect another, or that customers don't make changes that might prevent the vendor from supporting the system. Azure SQL Database gives us a database only, no instance features, though we do see a virtual master database.

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