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

Stonebraker & Hellerstein, eds.

Write-Ahead Logging (WAL)

The Write-Ahead Logging Protocol:

Must force the log record for an update before the corresponding data page gets to disk.
Must write all log records for a Xact before commit.

#1 guarantees Atomicity.

#2 guarantees Durability.

Exactly how is logging (and recovery!) done?

We’ll study the ARIES algorithms.

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