Consider a transaction T1 that committed prior to checkpoint. The <T1 commits> record appears in the log before the <checkpoint> record. Any modifications made by T1 must have been written to the stable storage either with the checkpoint or prior to it. Thus at recovery time ____________
A. There is a need to perform an undo operation on T1
B. There is a need to perform a redo operation on T1
C. There is no need to perform an undo and redo operation on T1
D. All of the mentioned
Answer:C
Consider a transaction T1 that committed prior to checkpoint. The <T1 commits> record appears in the log before the <checkpoint> record. Any modifications made by T1 must have been written to the stable storage either with the checkpoint or prior to it. Thus at recovery time ____________
A. There is a need to perform an undo operation on T1 B. There is a need to perform a redo operation on T1 C. There is no need to perform an undo and redo operation on T1 D. All of the mentioned