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Document need for periodic REINDEX in VACUUM FULL cases.

This commit is contained in:
Bruce Momjian 2007-01-31 04:13:28 +00:00
parent e2d6898827
commit 8c14912cc1
2 changed files with 6 additions and 5 deletions

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@ -1,4 +1,4 @@
<!-- $PostgreSQL: pgsql/doc/src/sgml/maintenance.sgml,v 1.64 2006/11/05 22:42:07 tgl Exp $ -->
<!-- $PostgreSQL: pgsql/doc/src/sgml/maintenance.sgml,v 1.64.2.1 2007/01/31 04:13:28 momjian Exp $ -->
<chapter id="maintenance">
<title>Routine Database Maintenance Tasks</title>
@ -613,9 +613,7 @@ analyze threshold = analyze base threshold + analyze scale factor * number of tu
for inefficient use of space: if all but a few index keys on a page have
been deleted, the page remains allocated. So a usage pattern in which all
but a few keys in each range are eventually deleted will see poor use of
space. The potential for bloat is not indefinite &mdash; at worst there
will be one key per page &mdash; but it may still be worthwhile to schedule
periodic reindexing for indexes that have such usage patterns.
space. For such usage patterns, periodic reindexing is recommended.
</para>
<para>

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@ -1,5 +1,5 @@
<!--
$PostgreSQL: pgsql/doc/src/sgml/ref/vacuum.sgml,v 1.43 2006/11/05 22:42:07 tgl Exp $
$PostgreSQL: pgsql/doc/src/sgml/ref/vacuum.sgml,v 1.43.2.1 2007/01/31 04:13:28 momjian Exp $
PostgreSQL documentation
-->
@ -167,6 +167,9 @@ VACUUM [ FULL ] [ FREEZE ] [ VERBOSE ] ANALYZE [ <replaceable class="PARAMETER">
most of the rows in a table and would like the table to physically shrink
to occupy less disk space. <command>VACUUM FULL</command> will usually
shrink the table more than a plain <command>VACUUM</command> would.
The <option>FULL</option> option does not shrink indexes; a periodic
<command>REINDEX</> is still recommended. In fact, it is often faster
to drop all indexes, <command>VACUUM FULL</>, and recreate the indexes.
</para>
<para>