Vertical scaling can be of two types: scale up or scale down service tiers, and vertical partitions.
Scaling up a service tier refers to switching to a higher service tier, for example, switching from Basic to Standard S0 or switching from Standard S0 to Standard S1.
Scaling down a service tier refers to switching to a lower service tier, for example, switching from Standard S1 to Standard S0, or switching from Standard S0 to Basic.
Scaling up a service tier allows you to maintain or improve database performance in peak business hours, and scaling down a service tier allows you to save costs during off-peak business hours.
The service tier is changed on the fly with zero downtime. When a service tier change request is sent to the Azure SQL Database, it first creates a copy of the database in the requested service tier and switches to the database in the new service tier once the copy is ready.
You are charged for the new service tier...