Consider a Transaction That Updates Each of the 100 Employees

question 52

Multiple Choice

Consider a transaction that updates each of the 100 employees' salaries in a table (there is one row per employee) under the deferred update mode and completes after a checkpoint.The system crashes after the checkpoint.What should the recovery procedure perform to make sure the transaction completes as desired?

• A) Redo from first log record
• B) Redo from first log record followed by execution of the transaction again
• C) Undo
• D) Undo followed by execution of the transaction again