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Complete merge of all old man page information.

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ecpg reference page still needs formatting.
This commit is contained in:
Thomas G. Lockhart
1999-07-22 15:09:15 +00:00
parent 2aa64f79f5
commit a27512e634
81 changed files with 2292 additions and 772 deletions
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34
doc/src/sgml/ref/cluster.sgml
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@@ -1,6 +1,11 @@
<!--
$Header: /cvsroot/pgsql/doc/src/sgml/ref/cluster.sgml,v 1.7 1999/07/22 15:09:06 thomas Exp $
Postgres documentation
-->
<refentry id="SQL-CLUSTER">
<refmeta>
<refentrytitle>
<refentrytitle id="sql-cluster-title">
CLUSTER
</refentrytitle>
<refmiscinfo>SQL - Language Statements</refmiscinfo>
@@ -10,12 +15,12 @@
CLUSTER
</refname>
<refpurpose>
Gives storage clustering advice to the backend
Gives storage clustering advice to the server
</refpurpose>
</refnamediv>
<refsynopsisdiv>
<refsynopsisdivinfo>
<date>1998-09-08</date>
<date>1999-07-20</date>
</refsynopsisdivinfo>
<synopsis>
CLUSTER <replaceable class="PARAMETER">indexname</replaceable> ON <replaceable class="PARAMETER">table</replaceable>
@@ -72,7 +77,7 @@ CLUSTER
</varlistentry>
<varlistentry>
<term><computeroutput>
ERROR: relation &lt;<replaceable class="PARAMETER">tablerelation_number</replaceable>&gt; inherits "invoice"
ERROR: relation &lt;<replaceable class="PARAMETER">tablerelation_number</replaceable>&gt; inherits "<replaceable class="PARAMETER">table</replaceable>"
</computeroutput></term>
<listitem>
<para>
@@ -85,12 +90,12 @@ ERROR: relation &lt;<replaceable class="PARAMETER">tablerelation_number</replace
</varlistentry>
<varlistentry>
<term><computeroutput>
ERROR: Relation x does not exist!
ERROR: Relation <replaceable class="PARAMETER">table</replaceable> does not exist!
</computeroutput></term>
<listitem>
<para>
<comment>
The relation complained of was not shown in the error message,
The specified relation was not shown in the error message,
which contained a random string instead of the relation name.
</comment>
</para>
@@ -111,12 +116,13 @@ ERROR: Relation x does not exist!
<para>
<command>CLUSTER</command> instructs <productname>Postgres</productname>
to cluster the class specified
by <replaceable class="parameter">classname</replaceable> approximately
by <replaceable class="parameter">table</replaceable> approximately
based on the index specified by
<replaceable class="parameter">indexname</replaceable>. The index must
already have been defined on
<replaceable class="parameter">classname</replaceable>.
</para>
<para>
When a class is clustered, it is physically reordered
based on the index information. The clustering is static.
@@ -150,7 +156,8 @@ ERROR: Relation x does not exist!
</para>
<para>
Another place <command>CLUSTER</command> is helpful is in cases where you use an
Another place where <command>CLUSTER</command> is helpful is in
cases where you use an
index to pull out several rows from a table. If you are
requesting a range of indexed values from a table, or a
single indexed value that has multiple rows that match,
@@ -173,11 +180,14 @@ ERROR: Relation x does not exist!
<para>
Another way to cluster data is to use
<programlisting>
SELECT ... INTO TABLE <replaceable class="parameter">temp</replaceable> FROM ... ORDER BY ...
SELECT <replaceable class="parameter">columnlist</replaceable> INTO TABLE <replaceable class="parameter">newtable</replaceable>
FROM <replaceable class="parameter">table</replaceable> ORDER BY <replaceable class="parameter">columnlist</replaceable>
</programlisting>
This uses the <productname>Postgres</productname> sorting code in
ORDER BY to match the index, and is much faster for
which uses the <productname>Postgres</productname> sorting code in
the ORDER BY clause to match the index, and which is much faster for
unordered data. You then drop the old table, use
<command>ALTER TABLE/RENAME</command>
to rename <replaceable class="parameter">temp</replaceable> to the old name, and
@@ -205,8 +215,6 @@ CLUSTER emp_ind ON emp;
<title>
Compatibility
</title>
<para>
</para>
<refsect2 id="R2-SQL-CLUSTER-4">
<refsect2info>