Transaction Processing Concepts, Concurrency and Recovery Of the read-item, writ
ID: 3690533 • Letter: T
Question
Transaction Processing Concepts, Concurrency and Recovery
Of the read-item, write-item, lock-item, unlock-item, initiate-transaction, and commit-transaction operations in a schedule or log, which can be redone? Undone? A. Only writes are redone/undone. B. Redone: read, write, lock, unlock; Undone: initiate, commit. C. Redone: read, lock, unlock, initiate, commit, write Undone: write D. Redone: Write, commit, read, initiate Undone: Write E. Write items and commit-transactions can be redone and undone.Explanation / Answer
Ans-> B: Redone: read, write, lock, unlock,
Undone: initiate, commit
Undo is a command in many computer programs. It erases the last change done to the document reverting it to an older state. In some more advanced programs such as graphic processing, undo will negate the last command done to the file being edited.
The opposite of undo is redo. The redo command reverses the undo or advances the buffer to a more current state.