11<!--
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2+ $Header: /cvsroot/pgsql/doc/src/sgml/ref/vacuum.sgml,v 1.8 2000/04/05 21:51:11 momjian Exp $
33Postgres documentation
44-->
55
@@ -51,8 +51,6 @@ VACUUM [ VERBOSE ] ANALYZE [ <replaceable class="PARAMETER">table</replaceable>
5151 <para>
5252Updates column statistics used by the optimizer to
5353determine the most efficient way to execute a query.
54- The statistics represent the disbursion of the data in each column.
55- This information is valuable when several execution paths are possible.
5654 </para>
5755 </listitem>
5856 </varlistentry>
@@ -158,6 +156,13 @@ NOTICE: Index <replaceable class="PARAMETER">index</replaceable>: Pages 28;
158156 tuples and number of pages stored in all classes.
159157 </para>
160158
159+
160+ <para>
161+ <command>VACUUM ANALYZE</command> collects statistics representing the
162+ disbursion of the data in each column.
163+ This information is valuable when several query execution paths are possible.
164+ </para>
165+
161166 <para>
162167 Running <command>VACUUM</command>
163168 periodically will increase the speed of the database in processing user queries.
@@ -179,11 +184,12 @@ NOTICE: Index <replaceable class="PARAMETER">index</replaceable>: Pages 28;
179184 query may be executed at any time, however. In particular, after
180185 copying a large class into <productname>Postgres</productname>
181186 or after deleting a large number of
182- records, it may be a good idea to issue a <command>VACUUM</command>
187+ records, it may be a good idea to issue a <command>VACUUM ANALYZE </command>
183188 query. This will update the system catalogs with the results of all
184189 recent changes, and allow the <productname>Postgres</productname>
185190 query optimizer to make better choices in planning user queries.
186191 </para>
192+
187193 </refsect2>
188194 </refsect1>
189195