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

Stonebraker & Hellerstein, eds.

Basic Idea: Logging

Record REDO and UNDO information, for every update, in a log.

Sequential writes to log (put it on a separate disk).
Minimal info (diff) written to log, so multiple updates fit in a single log page.

Log: An ordered list of REDO/UNDO actions

Log record contains: <, pageID, offset, length, old data, new data>
and additional control info (which we’ll see soon).

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