Snapshot backups - do I need equivalent database size disk space?
Snapshot backups are introduced in SQL Server 2005 version that uses:
The underlying backup technology creates an instantaneous copy of the data that is being backed up. The instantaneous copying is typically accomplished by splitting a mirrored set of disks or by creating a copy of a disk block when it is written. This preserves the original. At restore time, the original is made available immediately and synchronization of the underlying disks occurs in the background. This results in almost instantaneous restore operations.
So there are few questions at our end asking how much disk space is needed for these snapshot backups? The database we have is a 50gb in size which is used for Reporting purpose and on day-to-day basis they need to perform snapshot for the queries.
Guess what, you don't need 50gb available free space on the disk. Refer to the BOL article for complete information.
Also on the usage of snapshot backup database that when a SELECT statement is issued against a database snapshot, no locks are ever issued—regardless of whether the data page being read is located in the source database data file or the snapshot database data file. Because no locks are issued on the read-only database snapshot, snapshots are a great candidate for reporting solutions.