Backups versus Snapshots
A backup contains all the rowstore data in-memory (of committed transactions) as well as the columnstore blobs.
A snapshot contains only the rowstore data in-memory (of committed transactions).
Backups are a safety measure for restoring the cluster in case some major cluster-wide issue occurs.
SNAPSHOT truncates the transaction log.
ALTER TABLE), or before you perform maintenance operations that require restarting the leaf nodes.
Another recommendation is to take a backup of the databases involved beforehand, then after any schema and data changes have been performed successfully, take snapshots as well to ensure that the next time you recover a cluster, it does not have to replay all the recent changes.
Snapshots run in a matter of minutes, unlike backups which can take several hours.
Restoring from a snapshot is not supported, it can be done only from a backup.
Last modified: June 22, 2022