RestorableDroppedDatabases in Azure SQL DB & their naming convention
Published Mar 18 2024 01:09 PM 967 Views

Issue

An issue was reported recently where the customer complained that in their cost analysis report of their Azure SQL DBs, the db name appears appended with a comma(,) and a number. While they agreed with the DB name in the report, they didn’t understand the number after the comma and its significance. This is how the cost analysis report looks like:

Tanayankar_Chakraborty_0-1710733150204.png

 

Workaround/Explanation

RestorableDroppedDatabases is how Azure identifies internally (Purely for future restore purposes), a DB that was dropped.

Moreover, we bill for backups even after the database is dropped. This is because we allow customers to restore dropped databases and must retain backups to do so.

Once dropped, the backup charges will slowly decrease until days_since_dropped > backup_retention_days.

 

This charge will be identified by resourceUri of the restorableDroppedDatabase, e.g

 /subscriptions/<Sub ID>/resourceGroups/<RG-Name>/providers/Microsoft.Sql/servers/<ServerName>/restorableDroppedDatabases/<DB Name>,<number>

 

In the case above, after doing some analysis we figured that the DB in question was dropped and restored (within the backup retention duration of the dropped database).

Also, in the cost report above, the end number (after comma) is hash value of dropped time so that we can distinguish which dropped database customer wants to restore. This number is purely for internal use.

 

References

Restorable Dropped Databases - List By Server - REST API (Azure SQL Database) | Microsoft Learn

Restore a database from a backup - Azure SQL Database | Microsoft Learn

 

Version history
Last update:
‎Mar 18 2024 01:09 PM