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copy-only-backups-sql-server.md

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title description author ms.author ms.reviewer ms.date ms.service ms.subservice ms.topic helpviewer_keywords monikerRange
Copy-only backups
A copy-only backup is a SQL Server backup that is independent of the sequence of SQL Server backups. It doesn't affect how later backups are restored.
MashaMSFT
mathoma
randolphwest
12/28/2023
sql
backup-restore
conceptual
copy-only backups [SQL Server]
COPY_ONLY option [BACKUP statement]
backups [SQL Server], copy-only backups
=azuresqldb-mi-current || >=sql-server-2016 || >=sql-server-linux-2017

Copy-only backups

[!INCLUDE SQL Server SQL MI]

A copy-only backup is a [!INCLUDE ssNoVersion] backup that is independent of the sequence of conventional [!INCLUDE ssNoVersion] backups. Usually, taking a backup changes the database and affects how later backups are restored. However, occasionally, it's useful to take a backup for a special purpose without affecting the overall backup and restore procedures for the database. Copy-only backups serve this purpose.

The types of copy-only backups are as follows:

  • Copy-only full backups (all recovery models)

    • A copy-only backup can't serve as a differential base or differential backup and doesn't affect the differential base.

    • Restoring a copy-only full backup is the same as restoring any other full backup.

  • Copy-only log backups (full recovery model and bulk-logged recovery model only)

    • A copy-only log backup preserves the existing log archive point and, therefore, doesn't affect the sequencing of regular log backups. Copy-only log backups are typically unnecessary. Instead, you can create a new routine log backup (using WITH NORECOVERY) and use that backup together with any previous log backups that are required for the restore sequence. However, a copy-only log backup can sometimes be useful for performing an online restore. For more information, follow the instructions in the article Example: Online restore of a read-write file (full recovery model), using the copy-only backup files instead.

    • The transaction log is never truncated after a copy-only backup.

Copy-only backups are recorded in the is_copy_only column of the backupset table.

Important

In [!INCLUDE ssazuremi-md], copy-only backups can't be created for a database encrypted with service-managed Transparent Data Encryption (TDE). Service-managed TDE uses internal key for encryption of data, and that key can't be exported, so you couldn't restore the backup anywhere else. Consider using customer-managed TDE instead to be able to create copy-only backups of encrypted databases, but make sure to have encryption key available for later restore.

Create a copy-only backup

You can create a copy-only backup with [!INCLUDE ssManStudioFull], [!INCLUDE azure-data-studio], [!INCLUDE tsql], or PowerShell.

A. Use SQL Server Management Studio

In this example, a copy-only backup of the Sales database is backed up to disk at the default backup location.

  1. In Object Explorer, connect to an instance of the SQL Server Database Engine and then expand that instance.

  2. Expand Databases, right-click Sales, point to Tasks, and then select Back Up....

  3. On the General page in the Source section, check the Copy-only backup checkbox.

  4. Select OK.

B. Use Transact-SQL

This example creates a copy-only backup for the Sales database utilizing the COPY_ONLY parameter. A copy-only backup of the transaction log is taken as well.

BACKUP DATABASE Sales
TO DISK = 'E:\BAK\Sales_Copy.bak'
WITH COPY_ONLY;

BACKUP LOG Sales
TO DISK = 'E:\BAK\Sales_LogCopy.trn'
WITH COPY_ONLY;

Note

COPY_ONLY has no effect when specified with the DIFFERENTIAL option.

C. Use Transact-SQL and Azure SQL Managed Instance

Azure SQL Managed Instance supports taking COPY_ONLY full backups. The example performs a COPY_ONLY backup of MyDatabase to the Microsoft Azure Blob Storage. The storage Account name is mystorageaccount. The container is called myfirstcontainer. A storage access policy has been created with read, write, delete, and list rights. The [!INCLUDEssNoVersion] credential, https://mystorageaccount.blob.core.windows.net/myfirstcontainer, was created using a Shared Access Signature that is associated with the Storage Access Policy secret. For information on [!INCLUDEssNoVersion] backup to the Microsoft Azure Blob Storage, see SQL Server Backup and Restore with Microsoft Azure Blob Storage and SQL Server Backup to URL.

-- Prerequisite to have write permissions
CREATE CREDENTIAL [https://mystorageaccount.blob.core.windows.net/myfirstcontainer]
WITH IDENTITY = 'SHARED ACCESS SIGNATURE',
SECRET = 'sp=...' -- Enter your secret SAS token here.

BACKUP DATABASE MyDatabase
TO URL = 'https://mystorageaccount.blob.core.windows.net/myfirstcontainer/MyDatabaseBackup.bak'
WITH STATS = 5, COPY_ONLY;

To take a copy-only backup divided into multiple stripes, use this example:

BACKUP DATABASE MyDatabase
TO URL = 'https://mystorageaccount.blob.core.windows.net/myfirstcontainer/MyDatabase-01.bak',
URL = 'https://mystorageaccount.blob.core.windows.net/myfirstcontainer/MyDatabase-02.bak',
URL = 'https://mystorageaccount.blob.core.windows.net/myfirstcontainer/MyDatabase-03.bak',
URL = 'https://mystorageaccount.blob.core.windows.net/myfirstcontainer/MyDatabase-04.bak'
WITH COPY_ONLY;

D. Use PowerShell

This example creates a copy-only backup for the Sales database utilizing the -CopyOnly parameter.

Backup-SqlDatabase -ServerInstance 'SalesServer' -Database 'Sales' -BackupFile 'E:\BAK\Sales_Copy.bak' -CopyOnly

Related tasks

Create a full or log backup

View copy-only backups

Set up and use the SQL Server PowerShell provider

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