redbookcover.gif (13955 bytes) Readings in Database Systems, 3rd Edition

Stonebraker & Hellerstein, eds.

Example of Recovery

begin_checkpoint
end_checkpoint
update: T1 writes P5
update T2 writes P3
T1 abort
CLR: Undo T1 LSN 10
T1 End
update: T3 writes P1
update: T2 writes P5
CRASH, RESTART

LSN LOG

00
05
10
20
30
40
45
50
60

Xact Table
lastLSN
status
Dirty Page Table
recLSN
flushedLSN

ToUndo

prevLSNs

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© 1998, Joseph M. Hellerstein.  Last modified 08/17/98.
Feedback welcomed.