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Chapter 24: Database Snapshots
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Any data stored outside the application will not be rolled back when the database snapshot
is rolled back. If there are files created and stored on the file system outside of the data-
base (not using FILESTREAM and File Table) or somewhere on the network, these files will
not be removed or updated when the database is rolled back.Summary
Database snapshots enable you to create point-in-time, read-only versions of a database.
You can use them for reporting, recovery, and comparison functionality. Some key
takeaways from this chapter follow:■ Database snapshots enable maintaining readable point-in-time versions of a
production database for reporting and recovery purposes.
■ Database snapshots enable reporting on the mirror database that is not otherwise
possible.
■ Database snapshots enable you to restore the database to a specific point in time.■ (^) Although database snapshots are powerful and flexible, they are I/O-intensive.
If multiple database snapshots are created on a source database that is heavily
updated, the I/O load increases and may impact the performance of the system.
Like any other feature, it is highly recommended you get a performance baseline of the
environment before and after creating database snapshots and let your performance data
help you decide whether or not you should use database snapshots.
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