Explain the different types of BACKUPs available in SQL Server.Types of backups available in SQL Server:
- Complete: This creates a complete stand alone image of the database. This backup is self dependent and can be restored to either the same or a new database on same or other server.
- Differential: This backs up only the modified contents since the last backup. They do not provide much flexibility.
Transaction log: This backs up all transaction logs since the previous transaction log backup or the complete transaction log backup if there has not been one in past.
- Files and Filegroups backup: This option is suitable when time constraints are high and one cannot afford to perform a complete database backup. It also needs transaction logs backup to take place to make it worth choosing this option. After restoring file backup, apply transaction logs to roll the file contents forward to make it consistent with the database..
Explain the different types of BACKUPs available in SQL Server. Complete database backup: This type of backup will backup all the information in the database. Used most commonly for disaster recovery and takes the longest time to backup.
Differential databse backup: The database is divided into partitions that have been modified since last complete backup. Most suitable for large databases. The most recent differential backup contains the changes from previous backups.
Transaction log backups: Backups only the changes logged in the transaction log. The transaction log has all changes logged about a database. Once the changes are accommodated on the database, the log is truncated or backed up.
File/File Group backups: used to recover individual files or file groups. Each filegroup can be individually backed up. This helps in recovery only the required file or filegroup for disaster recovery.