Optimize backup storage costs for Azure SQL Database and Azure SQL Managed Instance
Backup storage costs depend on the provisioned database pricing tier and type. For the DTU model, the Azure SQL Database backup storage cost is included in the pricing tier. With the vCore model, Microsoft gives you free backup storage, which is equal to the size of your maximum provisioned database storage or reserved maximum storage for Azure SQL Managed Instance. For example, if you have a 100 GB standard Azure SQL database, you get 100 GB of free backup storage, and the same applies to the reserved total space for Azure SQL Managed Instance. You can control the free backup storage size by limiting the retention period of backups.
For single databases, this equation is used to calculate the total billable backup storage usage:
Total billable backup storage size = (size of full backups + size of differential backups + size of log backups) - maximum data storage
For pooled databases, the total...