This topic describes how to restore data to an existing instance from a full or differential backup set. ## **Background Information** SQL Server provides the following restore methods: * Restore from a backup set: This method allows you to restore an entire instance or specific databases to a new or existing instance from a specified backup set. The data in the restored instance is consistent with the data from the backup file. For more information, see [Restore to a new instance from a backup Set](https://docs.volcengine.com/docs/6899/141474) and [Restore to an Existing Instance from a backup set](https://docs.volcengine.com/docs/6899/1130117). * Restore to a point in time: This method allows you to restore an entire instance or specific databases to a new or existing instance as they were at a specified point in time. The data in the restored instance is consistent with the data at the specified point in time. For more information, see [Restore a new instance to a point in time](https://docs.volcengine.com/docs/6899/153379) and [Restore an existing instance to a point in time](https://docs.volcengine.com/docs/6899/1130119). ## **Prerequisites** * The target instance has been created and its status is **Running**. For detailed operations, see [Create an instance](https://docs.volcengine.com/docs/6899/141335). * The original instance must have at least one full or differential backup. ## **Precautions** * During the restoration process, the status of the target instance is **Recovering**. * Restoring system databases and the rdsadmin database is not currently supported. * Do not operate on the renamed destination database during restoration, as this may cause data conflicts or restoration failure. * If you restore to the original instance, the restored database name cannot be the same as the original database name or any existing database names in the instance. If you restore to an existing non\-original instance, the restored database name can be the same as the original one, but it cannot be the same as any existing database names in the target instance. By default, the restored database is named `DBName_bak{date}{minute}{second}`, for example, `DBName_bak20230718152102`. You can also customize the database name. * The recovery process will impose a certain amount of pressure on the target instance. It is recommended to perform backup recovery during off\-peak business hours. * When restoring to an existing instance, you can only select an instance with the same or a higher compatible version than the original instance. You cannot select an instance with a lower compatible version. * The number of databases to restore must be less than or equal to the remaining database quota of the target instance. ## Steps 1. Log on to the [RDS for SQL Server console](https://console.volcengine.com/db/sql-server). 2. In the upper\-left corner of the top menu bar, select the target project and region. 3. In the left navigation pane, click **Instances**. 4. On the **Instances** page, click the name of the target instance. 5. On the **Summary** page, click **Backups**. 6. On the **Backups** tab, click **Restore to existing instances**. 7. On the **Recovery to Existing Instances** page, configure the following parameters. |**Parameter** |**Description** | |---|---| |**Restore method** |Select **By backup set**. | |**Backup set** |Select a target **full backup** or **differential backup** from the dropdown list.

tip

After you select a target backup set, the All databases section displays all restorable databases from the backup set, excluding system and rdsadmin databases.

| |**Select instance** |Restore the backup to the original instance or other existing instance as needed. Fuzzy search for instances is supported.

tip

When restoring to an existing instance, you can only select an instance with the same or a higher compatible version than the original instance. You cannot select an instance with a lower compatible version. The year version and product edition of the compatible version must both be no lower than those of the original instance:

Year version: 2019 < 2022

Product edition: Web Edition < Standard Edition < Enterprise Edition

For example:

If the compatible version of the original instance is 2022 Standard Edition, you can select an instance with a compatible version of 2022 Standard Edition, 2022 Enterprise Edition.

If the compatible version of the original instance is 2019 Enterprise Edition, you can select an instance with a compatible version of 2019 Enterprise Edition, 2022 Enterprise Edition.

| |**Select database** |You can select to restore a single database, multiple databases, or all databases from an instance. Select the databases to restore in the **All databases** area, and confirm the databases and their names in the **Selected database** area.

tip

If you restore to the original instance, the restored database name cannot be the same as the original database name or any existing database names in the instance. If you restore to an existing non\-original instance, the restored database name can be the same as the original one, but it cannot be the same as any existing database names in the target instance. By default, the restored database is named DBName_bak{date}{minute}{second}, for example, DBName_bak20230718152102. In the Selected database area, you can rename the restored database. The name must follow these naming conventions:

Start with a letter and end with a letter or digit.

The length must be between 2 and 60 characters.

Consists of letters, numbers, and underscores (_).

You can not use reserved words, such as master, msdb, model, tempdb,resource, rdsadmin, and distribution.

| 8. Click **Submit**.