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-rw-r--r--doc/src/sgml/ref/create_index.sgml110
1 files changed, 56 insertions, 54 deletions
diff --git a/doc/src/sgml/ref/create_index.sgml b/doc/src/sgml/ref/create_index.sgml
index fda1c656110..65ce7687637 100644
--- a/doc/src/sgml/ref/create_index.sgml
+++ b/doc/src/sgml/ref/create_index.sgml
@@ -14,41 +14,33 @@
</REFPURPOSE>
<REFSYNOPSISDIV>
<REFSYNOPSISDIVINFO>
- <DATE>1998-04-15</DATE>
+ <DATE>1998-09-09</DATE>
</REFSYNOPSISDIVINFO>
<SYNOPSIS>
- CREATE [UNIQUE] INDEX <replaceable class="parameter">index_name</replaceable>
- ON <replaceable class="parameter">table</replaceable> [USING <replaceable class="parameter">acc_name</replaceable> ]
- ( <replaceable class="parameter">column</replaceable> [<replaceable class="parameter">ops_name</replaceable>] [, ...] )
-
- CREATE [UNIQUE] INDEX <replaceable class="parameter">index_name</replaceable>
- ON <replaceable class="parameter">table</replaceable> [USING <replaceable class="parameter">acc_name</replaceable> ]
- ( <replaceable class="parameter">func_name</replaceable>( <replaceable class="parameter">column</replaceable> [, ... ]) <replaceable class="parameter">ops_name</replaceable> )
+CREATE [ UNIQUE ] INDEX <replaceable class="parameter">index_name</replaceable>
+ ON <replaceable class="parameter">table</replaceable> [ USING <replaceable class="parameter">acc_name</replaceable> ]
+ ( <replaceable class="parameter">column</replaceable> [ <replaceable class="parameter">ops_name</replaceable>] [, ...] )
+CREATE [ UNIQUE ] INDEX <replaceable class="parameter">index_name</replaceable>
+ ON <replaceable class="parameter">table</replaceable> [ USING <replaceable class="parameter">acc_name</replaceable> ]
+ ( <replaceable class="parameter">func_name</replaceable>( <replaceable class="parameter">column</replaceable> [, ... ]) <replaceable class="parameter">ops_name</replaceable> )
</SYNOPSIS>
<REFSECT2 ID="R2-SQL-CREATEINDEX-1">
<REFSECT2INFO>
- <DATE>1998-04-15</DATE>
+ <DATE>1998-09-09</DATE>
</REFSECT2INFO>
<TITLE>
Inputs
</TITLE>
<PARA>
- </PARA>
- <VARIABLELIST>
- <VARLISTENTRY>
- <TERM>
- </TERM>
- <LISTITEM>
- <PARA>
<VARIABLELIST>
<VARLISTENTRY>
<TERM>
- <function>UNIQUE</function>
+ UNIQUE
</TERM>
<LISTITEM>
<PARA>
- <function>UNIQUE</function> causes the system to check for
+ Causes the system to check for
duplicate values when the index is created (if data
already exist) and each time data is added. Attempts to
insert or update non-duplicate data will generate an
@@ -134,17 +126,18 @@
An associated operator class.
The following select list returns all ops_names:
- <programlisting>
- SELECT am.amname AS acc_name,
- opc.opcname AS ops_name,
- opr.oprname AS ops_comp
- FROM pg_am am, pg_amop amop,
- pg_opclass opc, pg_operator opr
- WHERE amop.amopid = am.oid AND
- amop.amopclaid = opc.oid AND
- amop.amopopr = opr.oid
- ORDER BY acc_name, ops_name, ops_comp
- </programlisting>
+<programlisting>
+SELECT am.amname AS acc_name,
+ opc.opcname AS ops_name,
+ opr.oprname AS ops_comp
+ FROM pg_am am, pg_amop amop,
+ pg_opclass opc, pg_operator opr
+ WHERE amop.amopid = am.oid AND
+ amop.amopclaid = opc.oid AND
+ amop.amopopr = opr.oid
+ ORDER BY acc_name, ops_name, ops_comp
+</programlisting>
+
</PARA>
</LISTITEM>
</VARLISTENTRY>
@@ -160,14 +153,12 @@
</LISTITEM>
</VARLISTENTRY>
</variablelist>
- </LISTITEM>
- </VARLISTENTRY>
- </VARIABLELIST>
+
</REFSECT2>
<REFSECT2 ID="R2-SQL-CREATEINDEX-2">
<REFSECT2INFO>
- <DATE>1998-04-15</DATE>
+ <DATE>1998-09-09</DATE>
</REFSECT2INFO>
<TITLE>
Outputs
@@ -177,6 +168,7 @@
<VARIABLELIST>
<VARLISTENTRY>
<TERM>
+<replaceable>status</replaceable>
</TERM>
<LISTITEM>
<PARA>
@@ -210,14 +202,23 @@
<REFSECT1 ID="R1-SQL-CREATEINDEX-1">
<REFSECT1INFO>
- <DATE>1998-04-15</DATE>
+ <DATE>1998-09-09</DATE>
</REFSECT1INFO>
<TITLE>
Description
</TITLE>
<PARA>
- This command constructs an index called <replaceable class="parameter">index_name</replaceable>.
- </PARA>
+ This command constructs an index
+ <replaceable class="parameter">index_name</replaceable>.
+on the specified
+<replaceable class="parameter">table</replaceable>.
+
+<tip>
+<para>
+Indices are primarily used to enhance database performance.
+But inappropriate use will result in slower performance.
+</tip>
+
<para>
In the first syntax shown above, the key fields for the
index are specified as column names; a column may also have
@@ -242,7 +243,7 @@
<REFSECT2 ID="R2-SQL-CREATEINDEX-3">
<REFSECT2INFO>
- <DATE>1998-04-15</DATE>
+ <DATE>1998-09-09</DATE>
</REFSECT2INFO>
<TITLE>
Notes
@@ -252,10 +253,8 @@
indices. Up to 7 keys may be specified.
</PARA>
<para>
- Use the <citerefentry>
- <refentrytitle>DROP INDEX</refentrytitle>
- </citerefentry>
- statement to remove indexes.
+ Use <command>DROP INDEX</command>
+ to remove an index.
</para>
</REFSECT2>
@@ -267,24 +266,27 @@
in the table <literal>films</literal>:
</PARA>
<ProgramListing>
- CREATE UNIQUE INDEX title_idx
- ON films (title);
+CREATE UNIQUE INDEX title_idx
+ ON films (title);
</ProgramListing>
+
+<!--
+<comment>
+Is this example correct?
+</comment>
<para>
To create a rtree index on a point attribute so that we
can efficiently use box operators on the result of the
conversion function:
</para>
<programlisting>
- CREATE INDEX pointloc
- ON points USING RTREE (point2box(location) box_ops);
-
- SELECT * FROM points
- WHERE point2box(points.pointloc) = boxes.box;
-<comment>
-Is this example correct?
-</comment>
+CREATE INDEX pointloc
+ ON points USING RTREE (point2box(location) box_ops);
+SELECT * FROM points
+ WHERE point2box(points.pointloc) = boxes.box;
</programlisting>
+-->
+
</REFSECT1>
<REFSECT1 ID="R1-SQL-CREATEINDEX-3">
@@ -296,16 +298,16 @@ Is this example correct?
<REFSECT2 ID="R2-SQL-CREATEINDEX-4">
<REFSECT2INFO>
- <DATE>1998-04-15</DATE>
+ <DATE>1998-09-09</DATE>
</REFSECT2INFO>
<TITLE>
SQL92
</TITLE>
<PARA>
- CREATE INDEX is a PostgreSQL language extension.
+ CREATE INDEX is a <productname>Postgres</productname> language extension.
</PARA>
<para>
- There is no CREATE INDEX command in SQL92.
+ There is no <command>CREATE INDEX</command> command in SQL92.
</para>
</refsect2>
</refsect1>
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