Review: The ACID properties
A tomicity: All actions in the Xact happen, or none happen.
C onsistency: If each Xact is consistent, and the DB starts consistent, it ends up consistent.
I solation: Execution of one Xact is isolated from that of other Xacts.
D urability: If a Xact commits, its effects persist.
The Recovery Manager guarantees Atomicity & Durability.