184 lines
5.8 KiB
Plaintext
184 lines
5.8 KiB
Plaintext
<!--
|
|
doc/src/sgml/ref/create_tablespace.sgml
|
|
PostgreSQL documentation
|
|
-->
|
|
|
|
<refentry id="sql-createtablespace">
|
|
<indexterm zone="sql-createtablespace">
|
|
<primary>CREATE TABLESPACE</primary>
|
|
</indexterm>
|
|
|
|
<refmeta>
|
|
<refentrytitle>CREATE TABLESPACE</refentrytitle>
|
|
<manvolnum>7</manvolnum>
|
|
<refmiscinfo>SQL - Language Statements</refmiscinfo>
|
|
</refmeta>
|
|
|
|
<refnamediv>
|
|
<refname>CREATE TABLESPACE</refname>
|
|
<refpurpose>define a new tablespace</refpurpose>
|
|
</refnamediv>
|
|
|
|
<refsynopsisdiv>
|
|
<synopsis>
|
|
CREATE TABLESPACE <replaceable class="parameter">tablespace_name</replaceable>
|
|
[ OWNER { <replaceable>new_owner</replaceable> | CURRENT_ROLE | CURRENT_USER | SESSION_USER } ]
|
|
LOCATION '<replaceable class="parameter">directory</replaceable>'
|
|
[ WITH ( <replaceable class="parameter">tablespace_option</replaceable> = <replaceable class="parameter">value</replaceable> [, ... ] ) ]
|
|
</synopsis>
|
|
</refsynopsisdiv>
|
|
|
|
<refsect1>
|
|
<title>Description</title>
|
|
|
|
<para>
|
|
<command>CREATE TABLESPACE</command> registers a new cluster-wide
|
|
tablespace. The tablespace name must be distinct from the name of any
|
|
existing tablespace in the database cluster.
|
|
</para>
|
|
|
|
<para>
|
|
A tablespace allows superusers to define an alternative location on
|
|
the file system where the data files containing database objects
|
|
(such as tables and indexes) can reside.
|
|
</para>
|
|
|
|
<para>
|
|
A user with appropriate privileges can pass
|
|
<replaceable class="parameter">tablespace_name</replaceable> to
|
|
<command>CREATE DATABASE</command>, <command>CREATE TABLE</command>,
|
|
<command>CREATE INDEX</command> or <command>ADD CONSTRAINT</command> to have the data
|
|
files for these objects stored within the specified tablespace.
|
|
</para>
|
|
|
|
<warning>
|
|
<para>
|
|
A tablespace cannot be used independently of the cluster in which it
|
|
is defined; see <xref linkend="manage-ag-tablespaces"/>.
|
|
</para>
|
|
</warning>
|
|
|
|
</refsect1>
|
|
|
|
<refsect1>
|
|
<title>Parameters</title>
|
|
|
|
<variablelist>
|
|
<varlistentry>
|
|
<term><replaceable class="parameter">tablespace_name</replaceable></term>
|
|
<listitem>
|
|
<para>
|
|
The name of a tablespace to be created. The name cannot
|
|
begin with <literal>pg_</literal>, as such names
|
|
are reserved for system tablespaces.
|
|
</para>
|
|
</listitem>
|
|
</varlistentry>
|
|
|
|
<varlistentry>
|
|
<term><replaceable class="parameter">user_name</replaceable></term>
|
|
<listitem>
|
|
<para>
|
|
The name of the user who will own the tablespace. If omitted,
|
|
defaults to the user executing the command. Only superusers
|
|
can create tablespaces, but they can assign ownership of tablespaces
|
|
to non-superusers.
|
|
</para>
|
|
</listitem>
|
|
</varlistentry>
|
|
|
|
<varlistentry>
|
|
<term><replaceable class="parameter">directory</replaceable></term>
|
|
<listitem>
|
|
<para>
|
|
The directory that will be used for the tablespace. The directory
|
|
must exist (<command>CREATE TABLESPACE</command> will not create it),
|
|
should be empty, and must be owned by the
|
|
<productname>PostgreSQL</productname> system user. The directory must be
|
|
specified by an absolute path name.
|
|
</para>
|
|
</listitem>
|
|
</varlistentry>
|
|
|
|
<varlistentry>
|
|
<term><replaceable class="parameter">tablespace_option</replaceable></term>
|
|
<listitem>
|
|
<para>
|
|
A tablespace parameter to be set or reset. Currently, the only
|
|
available parameters are <varname>seq_page_cost</varname>,
|
|
<varname>random_page_cost</varname>, <varname>effective_io_concurrency</varname>
|
|
and <varname>maintenance_io_concurrency</varname>.
|
|
Setting these values for a particular tablespace will override the
|
|
planner's usual estimate of the cost of reading pages from tables in
|
|
that tablespace, and the executor's prefetching behavior, as established
|
|
by the configuration parameters of the
|
|
same name (see <xref linkend="guc-seq-page-cost"/>,
|
|
<xref linkend="guc-random-page-cost"/>,
|
|
<xref linkend="guc-effective-io-concurrency"/>,
|
|
<xref linkend="guc-maintenance-io-concurrency"/>). This may be useful if
|
|
one tablespace is located on a disk which is faster or slower than the
|
|
remainder of the I/O subsystem.
|
|
</para>
|
|
</listitem>
|
|
</varlistentry>
|
|
</variablelist>
|
|
</refsect1>
|
|
|
|
<refsect1>
|
|
<title>Notes</title>
|
|
|
|
<para>
|
|
<command>CREATE TABLESPACE</command> cannot be executed inside a transaction
|
|
block.
|
|
</para>
|
|
</refsect1>
|
|
|
|
<refsect1>
|
|
<title>Examples</title>
|
|
|
|
<para>
|
|
To create a tablespace <literal>dbspace</literal> at file system location
|
|
<literal>/data/dbs</literal>, first create the directory using operating
|
|
system facilities and set the correct ownership:
|
|
<programlisting>
|
|
mkdir /data/dbs
|
|
chown postgres:postgres /data/dbs
|
|
</programlisting>
|
|
Then issue the tablespace creation command inside
|
|
<productname>PostgreSQL</productname>:
|
|
<programlisting>
|
|
CREATE TABLESPACE dbspace LOCATION '/data/dbs';
|
|
</programlisting>
|
|
</para>
|
|
|
|
<para>
|
|
To create a tablespace owned by a different database user, use a command
|
|
like this:
|
|
<programlisting>
|
|
CREATE TABLESPACE indexspace OWNER genevieve LOCATION '/data/indexes';
|
|
</programlisting></para>
|
|
</refsect1>
|
|
|
|
<refsect1>
|
|
<title>Compatibility</title>
|
|
|
|
<para>
|
|
<command>CREATE TABLESPACE</command> is a <productname>PostgreSQL</productname>
|
|
extension.
|
|
</para>
|
|
</refsect1>
|
|
|
|
<refsect1>
|
|
<title>See Also</title>
|
|
|
|
<simplelist type="inline">
|
|
<member><xref linkend="sql-createdatabase"/></member>
|
|
<member><xref linkend="sql-createtable"/></member>
|
|
<member><xref linkend="sql-createindex"/></member>
|
|
<member><xref linkend="sql-droptablespace"/></member>
|
|
<member><xref linkend="sql-altertablespace"/></member>
|
|
</simplelist>
|
|
</refsect1>
|
|
|
|
</refentry>
|