From: Bruce Momjian <bruce@momjian.us>
Date: Tue, 20 Apr 2004 04:25:47 +0000 (+0000)
Subject: Document partial indexes for IS NULL lookups.
X-Git-Tag: REL8_0_0BETA1~801
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=bb18b4739001cfbfb38584f467d53d97666cc114;p=postgresql

Document partial indexes for IS NULL lookups.
---

diff --git a/doc/src/sgml/ref/create_index.sgml b/doc/src/sgml/ref/create_index.sgml
index 34e12c6a5d..43583df54d 100644
--- a/doc/src/sgml/ref/create_index.sgml
+++ b/doc/src/sgml/ref/create_index.sgml
@@ -1,5 +1,5 @@
 <!--
-$PostgreSQL: pgsql/doc/src/sgml/ref/create_index.sgml,v 1.45 2004/04/20 01:00:26 momjian Exp $
+$PostgreSQL: pgsql/doc/src/sgml/ref/create_index.sgml,v 1.46 2004/04/20 04:25:47 momjian Exp $
 PostgreSQL documentation
 -->
 
@@ -77,11 +77,9 @@ CREATE [ UNIQUE ] INDEX <replaceable class="parameter">name</replaceable> ON <re
   </para>
 
   <para>
-   <literal>NULL</> values are not indexed by default.  The best way
-   to index <literal>NULL</> values is to create a partial index using
-   an <literal>IS NULL</> comparison.  <literal>IS NULL</> is more
-   of a function call than a value comparison, and this is why a partial
-   index works.
+   Indexes can not be used with <literal>IS NULL</> clauses by default.
+   The best way to use indexes in such cases is to create a partial index 
+   using an <literal>IS NULL</> comparison.
   </para>
 
   <para>