Recovery & Transaction Management

Recovery is the process of restoring the database to a correct and consistent state after a system failure (e.g., power outage, software crash). Recovery techniques ensure that the database's ACID properties are maintained. Key techniques include log-based recovery, checkpointing, and shadow paging.

Transaction Management is responsible for controlling the execution of transactions. A transaction is a single logical unit of work. Transaction Management ensures that transactions adhere to the ACID properties:

• Atomicity: All parts of a transaction are completed, or none are.
• Consistency: The database remains in a valid state before and after the transaction.
• Isolation: Concurrent transactions do not interfere with each other.
• Durability: Once a transaction is committed, its changes are permanent.