@ -1,27 +1,31 @@
<!-- doc/src/sgml/contrib.sgml --> <!-- doc/src/sgml/contrib.sgml -->
<appendix id="contrib"> <appendix id="contrib">
<title>Additional Supplied Modules</title> <title>Additional Supplied Modules and Extensions </title>
<para> <para>
This appendix and the next one contain information regarding the modules that This appendix and the next one contain information on the
can be found in the <literal>contrib</literal> directory of the optional components
found in the <literal>contrib</literal> directory of the
<productname>PostgreSQL</productname> distribution. <productname>PostgreSQL</productname> distribution.
These include porting tools, analysis utilities, These include porting tools, analysis utilities,
and plug-in features that are not part of the core PostgreSQL system, and plug-in features that are not part of the core PostgreSQL system.
mainly because they address a limited audience or are too experimental They are separate mainly
because they address a limited audience or are too experimental
to be part of the main source tree. This does not preclude their to be part of the main source tree. This does not preclude their
usefulness. usefulness.
</para> </para>
<para> <para>
This appendix covers extensions and other server plug-in modules found in This appendix covers extensions and other server plug-in module
libraries found in
<literal>contrib</literal>. <xref linkend="contrib-prog"/> covers utility <literal>contrib</literal>. <xref linkend="contrib-prog"/> covers utility
programs. programs.
</para> </para>
<para> <para>
When building from the source distribution, these components are not built When building from the source distribution, these optional
components are not built
automatically, unless you build the "world" target automatically, unless you build the "world" target
(see <xref linkend="build"/>). (see <xref linkend="build"/>).
You can build and install all of them by running: You can build and install all of them by running:
@ -46,41 +50,42 @@
<para> <para>
If you are using a pre-packaged version of <productname>PostgreSQL</productname>, If you are using a pre-packaged version of <productname>PostgreSQL</productname>,
these module s are typically made available as a separate subpackage, these component s are typically made available as a separate subpackage,
such as <literal>postgresql-contrib</literal>. such as <literal>postgresql-contrib</literal>.
</para> </para>
<para> <para>
Many modules supply new user-defined functions, operators, or types. Many components supply new user-defined functions, operators, or types,
To make use of one of these modules, after you have installed the code packaged as <firstterm>extensions</firstterm>.
To make use of one of these extensions, after you have installed the code
you need to register the new SQL objects in the database system. you need to register the new SQL objects in the database system.
This is done by executing This is done by executing
a <xref linkend="sql-createextension"/> command. In a fresh database, a <xref linkend="sql-createextension"/> command. In a fresh database,
you can simply do you can simply do
<programlisting> <programlisting>
CREATE EXTENSION <replaceable>module _name</replaceable>; CREATE EXTENSION <replaceable>extension _name</replaceable>;
</programlisting> </programlisting>
This command registers the new SQL objects in the current database only, This command registers the new SQL objects in the current database only,
so you need to run it in each database that you want so you need to run it in every database in which you want
the module's facilities to be available in . Alternatively, run it in the extension's facilities to be available . Alternatively, run it in
database <literal>template1</literal> so that the extension will be copied into database <literal>template1</literal> so that the extension will be copied into
subsequently-created databases by default. subsequently-created databases by default.
</para> </para>
<para> <para>
For all these modules, <command>CREATE EXTENSION</command> must be run For all extensions, the <command>CREATE EXTENSION</command> command must be
by a database superuser, unless the module is run by a database superuser, unless the extension is
considered <quote>trusted</quote>, in which case it can be run by any considered <quote>trusted</quote>. Trusted extensions can be run by any
user who has <literal>CREATE</literal> privilege on the current user who has <literal>CREATE</literal> privilege on the current
database. Module s that are trusted are identified as such in the database. Extension s that are trusted are identified as such in the
sections that follow. Generally, trusted module s are ones that cannot sections that follow. Generally, trusted extension s are ones that cannot
provide access to outside-the-database functionality. provide access to outside-the-database functionality.
</para> </para>
<para> <para>
Many module s allow you to install their objects in a schema of your Many extension s allow you to install their objects in a schema of your
choice. To do that, add <literal>SCHEMA choice. To do that, add <literal>SCHEMA
<replaceable>schema_name</replaceable></literal> to the <command>CREATE EXTENSION</command> <replaceable>schema_name</replaceable></literal> to the <command>CREATE EXTENSION</command>
command. By default, the objects will be placed in your current creation command. By default, the objects will be placed in your current creation
@ -88,11 +93,11 @@ CREATE EXTENSION <replaceable>module_name</replaceable>;
</para> </para>
<para> <para>
Note, however, that some of these module s are not <quote>extensions</quote> Note, however, that some of these component s are not <quote>extensions</quote>
in this sense, but are loaded into the server in some other way, for instance in this sense, but are loaded into the server in some other way, for instance
by way of by way of
<xref linkend="guc-shared-preload-libraries"/>. See the documentation of each <xref linkend="guc-shared-preload-libraries"/>. See the documentation of each
module for details. component for details.
</para> </para>
&adminpack; &adminpack;
Alvaro Herrera
3 years ago