Update hash warning in manual.

This commit is contained in:
Bruce Momjian 2002-06-21 16:52:00 +00:00
parent ebe4375fa1
commit 1415a8388f
2 changed files with 10 additions and 8 deletions

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@ -1,4 +1,4 @@
<!-- $Header: /cvsroot/pgsql/doc/src/sgml/indices.sgml,v 1.32 2002/06/21 03:25:53 momjian Exp $ -->
<!-- $Header: /cvsroot/pgsql/doc/src/sgml/indices.sgml,v 1.33 2002/06/21 16:52:00 momjian Exp $ -->
<chapter id="indexes">
<title id="indexes-title">Indexes</title>
@ -181,9 +181,10 @@ CREATE INDEX <replaceable>name</replaceable> ON <replaceable>table</replaceable>
</synopsis>
<note>
<para>
Testing has shown that hash indexes are slower than btree indexes,
and the size and build time for hash indexes is much worse. For
these reasons, hash index use is discouraged.
Testing has shown hash indexes to be similar or slower than btree
indexes, and the index size and build time for hash indexes is much
worse. Hash indexes also suffer poor performance under high
concurrency. For these reasons, hash index use is discouraged.
</para>
</note>
</para>

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@ -1,5 +1,5 @@
<!--
$Header: /cvsroot/pgsql/doc/src/sgml/ref/create_index.sgml,v 1.32 2002/06/21 03:25:53 momjian Exp $
$Header: /cvsroot/pgsql/doc/src/sgml/ref/create_index.sgml,v 1.33 2002/06/21 16:52:00 momjian Exp $
PostgreSQL documentation
-->
@ -330,9 +330,10 @@ ERROR: Cannot create index: 'index_name' already exists.
the <literal>=</literal> operator.
</para>
<para>
Testing has shown that hash indexes are slower than btree indexes,
and the size and build time for hash indexes is much worse. For
these reasons, hash index use is discouraged.
Testing has shown hash indexes to be similar or slower than btree
indexes, and the index size and build time for hash indexes is much
worse. Hash indexes also suffer poor performance under high
concurrency. For these reasons, hash index use is discouraged.
</para>
<para>