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

Stonebraker & Hellerstein, eds.

More on Steal and Force

STEAL (why enforcing Atomicity is hard)

To steal frame F: Current page in F (say P) is written to disk; some Xact holds lock on P.
What if the Xact with the lock on P aborts?
Must remember the old value of P at steal time (to support UNDOing the write to page P).

NO FORCE (why enforcing Durability is hard)

What if system crashes before a modified page is written to disk?
Write as little as possible, in a convenient place, at commit time,to support REDOing modifications.

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