determines which transactions to undo, which pages were dirty at the time of the crash, and the LSN from which the redo pass should start.

Related MCQs

•                      scheme that records only information about dirty pages and associated information and does not even require of writing dirty pages to disk.
•                      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.
• For correct behaviour during recovery, undo and redo operation must be
•                              rolls back all transactions that were incomplete at the time of crash.
• If                        are not obtained in undo operation it will cause problem in undo- phase.
• A concurrency-control policy such as this one leads to              performance since it forces transactions to wait for preceding transactions to finish before they can start.
• Whenever an update operation occurs on a page, the operation stores the LSN of its log record in the                field of the page.
• A special redo-only log record < Ti, Xj, V1> is written to the log, where V1 is the value being restored to data item Xj during the rollback. These log records are sometimes called
• Redo operations are performed exclusively using
• In order to undo the work of transaction after last commit which one should be used?