ARIES recovers from a system crash in three passes.

• Analysis pass: This pass determines which transactions to undo, which pages were dirty at the time of the crash, and the LSN from which the redo passshould start.

• Redo pass: This pass starts from a position determined during analysis, and performs a redo, repeating history, to bring the database to a state it was in
before the crash. • Undo pass: This pass rolls back all transactions that were incomplete at the time of crash.


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