Azure SQL Managed Instance is fully-managed SQL Server Database Engine hosted in Azure cloud. With Managed Instance you can easily add/remove cores associated to the instance and change the reserved size of the instance. You can use PowerShell to easily manage size of the instance and automate this process.
As a prerequisite, you need to have Azure SQL PowerShell libraries to configure Managed Instance. You would need to install Azure RM PowerShell and AzureRm.Sql module that contains the commands for updating properties of Managed Instance.
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