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Markup and editing adjustments...

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Thomas G. Lockhart
1998-09-16 14:43:12 +00:00
parent 5a68fd56cd
commit d2a907c6ad
18 changed files with 986 additions and 884 deletions
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110
doc/src/sgml/ref/create_index.sgml
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@@ -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>