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Databases are the lifeblood of modern IT infrastructure and ensuring their availability and functionality is crucial. Database issues, however, can cause disruptions, leading to downtime and failure. One of the key recovery strategies for such mishaps is to restore the database to its operational state, which is what this blog intends to guide you through, specifically for SQL Server Databases.
Return Backup Database to Operational State
The first method to restore a database focuses on using a full database backup. This is typically done as part of a disaster recovery plan, or when moving databases between systems or testing backups. Here’s how it can be done:
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RESTORE DATABASE YourDatabase FROM DISK = 'C:\BackupLocation\YourBackup.bak' |
This code will restore the “YourDatabase” from the backup file (“YourBackup.bak”) located in ‘C:\BackupLocation\’.
Restoring With NORECOVERY
In cases where you might want to restore multiple backup files – a full database backup, followed by a differential backup for example, you would need to use the NORECOVERY keyword. This will leave the database in a restoring state following the restore.
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RESTORE DATABASE YourDatabase FROM DISK = 'C:\BackupLocation\YourBackup.bak' WITH NORECOVERY |
Restoring a Differential Backup
Assuming you have restored a full backup with NORECOVERY, you can now apply a differential backup:
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RESTORE DATABASE YourDatabase FROM DISK = 'C:\BackupLocation\YourDiffBackup.bak' WITH RECOVERY |
This sequence of code will restore the initial database backup in a non-recoverable state to then apply the differential backup and finally recover the database to its operational state.
Restoring Transaction Log Backups
Normally, in addition to full and differential backups, transaction log backups are also taken. These can be restored after restoring full and differential backups:
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RESTORE LOG YourDatabase FROM DISK = 'C:\BackupLocation\YourTranLogBackup.bak' WITH RECOVERY |
This command will apply the backed-up transaction logs to the database, and then fully recover the database, making it accessible again.
Remember, it’s crucial to ensure that backups are fair, functional and conducted regularly. They serve as your last line of defense in scenarios where your database encounters issues or failures.
In conclusion, the SQL Server provides powerful and efficient commands and functionalities that can aid in the task of restoring your databases to their operational state.