Exercise 17.2.4:

The following is a sequence of undo-log records written by two transactions T and U:

< START T>; ; < START U>; ; ; ; ; < T ,E , 50>; .

Describe the action of the recovery manager, including changes to both disk and the log, if there is a crash and the last log record to appear on disk is:

(a) < START U>
(b)
(c) < T ,E , 50>
(d) .