There are several types of SQL backups commonly used to protect and restore data in a database. The specific types and terminology may vary slightly depending on the database management system (DBMS) being used, but the following are the most common types of SQL backups:
Full Backup: A full backup creates a complete copy of the entire database. It includes all data, schema objects, and database settings. Full backups provide a baseline for restoring the database to a specific point in time.
Differential Backup: A differential backup captures all changes made to the database since the last full backup. It backs up only the data that has changed, which reduces the backup size and duration compared to a full backup. To restore the database, you would need the most recent full backup along with the most recent differential backup.
Transaction Log Backup: In addition to full and differential backups, transaction log backups capture all the transactions that occur in the database. These backups record the sequence of changes made to the database, allowing for point-in-time recovery. Transaction log backups are typically taken at regular intervals and are essential for recovering a database to a specific point in time.
Copy-only Backup: A copy-only backup is an independent backup that does not affect the backup chain. It allows you to take a backup without interfering with the regular backup schedule or affecting the differential or transaction log backups. Copy-only backups are useful for creating ad hoc backups for specific purposes without disrupting the regular backup strategy.
File/Filegroup Backup: This type of backup allows you to back up individual database files or filegroups rather than the entire database. It provides flexibility in managing large databases by allowing selective backups and restores of specific filegroups or files.
Partial Backup: A partial backup backs up only the primary filegroup and any read/write filegroups. This type of backup is useful when dealing with large databases that have read-only filegroups or archived data that doesn't need to be backed up frequently.
It's important to note that the availability of these backup types may depend on the specific DBMS being used, as different database systems may have variations in their backup and restore capabilities.