//Database Management/ ARIES recovery algorithm logs

For questions 4-6, consider the execution of the ARIES recovery algorithm given the following log:

LSN	Log Record
00	begin_checkpoint
05	end_checkpoint
10	Update: T2 writes P4
20	Update: T1 writes P2
30	Update: T2 writes P1
40	T2 abort
50	Update: T4 writes P2
60	CLR: Undo T2 LSN 30
70	T4 commit
80	CLR: Undo T2 LSN 10
90	Update: T3 writes P3
100	T2 end
	X - crash, restart

For the questions below, when you are asked which log records are read, you are to supply the exact list of LSNs from log above. When data pages are asked for, you are to supply the exact list of page identifiers from the log above. And so on. Be specific and concrete in your answers, answering specifically for the provided log.

Operations can be identified using the LSN for the log record recording that operation. (So, of course, can the log record itself.)

No Generic statements or quotations Example: "all the pages" == 0 "P1, P2 and P3" == more than, assuming those are the pages read.

During Analysis: a) What log records are read? b) What are the contents of the Dirty Page Table (DPT) and the transaction table at the end of the analysis stage?

During Redo: a) What log records are read? b) What data pages are read? c) What operations are redone? (Assume no updates made it out to stable storage, like a hard disk, before the crash, except updates written to stable storage as part of a transaction commit.)

During Undo: a) What log records are read? b) What operations are undone?