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Fix typo, other minor improvements.

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This commit is contained in:
Neil Conway 2004-11-15 04:35:57 +00:00
parent f6474586ea
commit db1531f6d8
1 changed files with 12 additions and 12 deletions
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24
doc/src/sgml/wal.sgml
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@ -1,4 +1,4 @@
<!-- $PostgreSQL: pgsql/doc/src/sgml/wal.sgml,v 1.29 2004/08/08 04:34:43 tgl Exp $ --> <!-- $PostgreSQL: pgsql/doc/src/sgml/wal.sgml,v 1.30 2004/11/15 04:35:57 neilc Exp $ -->
<chapter id="wal"> <chapter id="wal">
<title>Write-Ahead Logging (<acronym>WAL</acronym>)</title> <title>Write-Ahead Logging (<acronym>WAL</acronym>)</title>
@ -104,17 +104,17 @@
</para> </para>
<para> <para>
<firstterm>Checkpoints</firstterm><indexterm><primary>checkpoint</></> are points in the sequence of <firstterm>Checkpoints</firstterm><indexterm><primary>checkpoint</></>
transactions at which it is guaranteed that the data files have are points in the sequence of transactions at which it is guaranteed
been updated with all information logged before the checkpoint. At that the data files have been updated with all information logged before
checkpoint time, all dirty data pages are flushed to disk and a the checkpoint. At checkpoint time, all dirty data pages are flushed to
special checkpoint record is written to the log file. As result, in disk and a special checkpoint record is written to the log file. As a
the event of a crash, the recoverer knows from what point in the result, in the event of a crash, the crash recovery procedure knows from
log (known as the redo record) it should start the REDO operation, what point in the log (known as the redo record) it should start the
since any changes made to data files before that record are already REDO operation, since any changes made to data files before that point
on disk. After a checkpoint has been made, any log segments written are already on disk. After a checkpoint has been made, any log segments
before the redo record are no longer needed and can be recycled or written before the redo record are no longer needed and can be recycled
removed. (When <acronym>WAL</acronym> archiving is being done, the or removed. (When <acronym>WAL</acronym> archiving is being done, the
log segments must be archived before being recycled or removed.) log segments must be archived before being recycled or removed.)
</para> </para>