The description in Section 18.6.1 of the Analysis phase made the simplifying assumption that no log records appeared between the begin checkpoint and end checkpoint records for the most recent complete checkpoint. The following questions explore how such records should be handled.
1. Explain why log records could be written between the begin checkpoint and end checkpoint records.
2. Describe how the Analysis phase could be modified to handle such records.
3. Consider the execution shown in Figure 18.4. Show the contents of the end checkpoint record.
4. Illustrate your modified Analysis phase on the execution shown in Figure 18.4.

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LSN LOG 十 begin-checkpoint 10 update : TI writes Pl 20T commit update: T2 writes P2 T end T2 abort update: T3 writes P3 40 50- 60 end checlkpoint 80 T3 commit CRASH, RESTART