Merge pull request #104894 from adeal/patch-2

Make the impact of LTR policy change more clear

Author: PRMerger19

articles/sql-database/sql-database-long-term-retention.md

@@ -22,7 +22,13 @@ Many applications have regulatory, compliance, or other business purposes that r
 
 ## How SQL Database long-term retention works
 
-Long-term backup retention (LTR) leverages the full database backups that are [automatically created](sql-database-automated-backups.md) to enable point-time restore (PITR). If an LTR policy is configured, these backups are copied to different blobs for long-term storage. The copy operation is a background job that has no performance impact on the database workload. The LTR backups are retained for a period of time set by the LTR policy. The LTR policy for each SQL database can also specify how frequently the LTR backups are created. To enable that flexibility you can define the policy using a combination of four parameters: weekly backup retention (W), monthly backup retention (M), yearly backup retention (Y), and week of year (WeekOfYear). If you specify W, one backup every week will be copied to the long-term storage. If you specify M, one backup during the first week of each month will be copied to the long-term storage. If you specify Y, one backup during the week specified by WeekOfYear will be copied to the long-term storage. Each backup will be kept in the long-term storage for the period specified by these parameters. Any change of the LTR policy applies to the future backups. For example, if the specified WeekOfYear is in the past when the policy is configured, the first LTR backup will be created next year. 
+Long-term backup retention (LTR) leverages the full database backups that are [automatically created](sql-database-automated-backups.md) to enable point-time restore (PITR). If an LTR policy is configured, these backups are copied to different blobs for long-term storage. The copy is a background job that has no performance impact on the database workload. The LTR policy for each SQL database can also specify how frequently the LTR backups are created.
+
+To enable LTR, you can define a policy using a combination of four parameters: weekly backup retention (W), monthly backup retention (M), yearly backup retention (Y), and week of year (WeekOfYear). If you specify W, one backup every week will be copied to the long-term storage. If you specify M, the first backup of each month will be copied to the long-term storage. If you specify Y, one backup during the week specified by WeekOfYear will be copied to the long-term storage. If the specified WeekOfYear is in the past when the policy is configured, the first LTR backup will be created in the following year. Each backup will be kept in the long-term storage according to the policy parameters that are configured when the LTR backup is created.
+
+> [!NOTE]
+> Any change to the LTR policy applies only to future backups. For example, if weekly backup retention (W), monthly backup retention (M), or yearly backup retention (Y) is modified, the new retention setting will only apply to new backups. The retention of existing backups will not be modified. If your intention is to delete old LTR backups before their retention period expires, you will need to [manually delete the backups](https://docs.microsoft.com/azure/sql-database/sql-database-long-term-backup-retention-configure#delete-ltr-backups).
+> 
 
 Examples of the LTR policy:
 
@@ -69,7 +75,7 @@ To learn how to configure long-term retention using the Azure portal or PowerShe
 
 ## Restore database from LTR backup
 
-To restore a database from the LTR storage, you can select a specific backup based on its timestamp. The database can be restored to any existing server under the same subscription as the original database. To learn how to restore your database from an LTR backup, using the Azure portal or PowerShell, see [Manage Azure SQL Database long-term backup retention](sql-database-long-term-backup-retention-configure.md).
+To restore a database from the LTR storage, you can select a specific backup based on its timestamp. The database can be restored to any existing server under the same subscription as the original database. To learn how to restore your database from an LTR backup, using the Azure portal, or PowerShell, see [Manage Azure SQL Database long-term backup retention](sql-database-long-term-backup-retention-configure.md).
 
 ## Next steps