<title>Description</title>
<para>
<command>ALTER TABLESPACE</command> can be used to change the definition of
a tablespace.
</para>
<para>
You must own the tablespace to change the definition of a tablespace.
To alter the owner, you must also be able to <literal>SET ROLE</literal>
to the new owning role.
(Note that superusers have these privileges automatically.)
</para>
</refsect1>
<refsect1>
<title>Parameters</title>
<variablelist>
<varlistentry>
<term><replaceable class="parameter">name</replaceable></term>
<listitem>
<para>
The name of an existing tablespace.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><replaceable class="parameter">new_name</replaceable></term>
<listitem>
<para>
The new name of the tablespace. The new name cannot
begin with <literal>pg_</literal>, as such names
are reserved for system tablespaces.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><replaceable class="parameter">new_owner</replaceable></term>
<listitem>
<para>
The new owner of the tablespace.
</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 how many concurrent I/Os are issued, 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>Examples</title>
<para>
Rename tablespace <literal>index_space</literal> to <literal>fast_raid</literal>:
<programlisting>
ALTER TABLESPACE index_space RENAME TO fast_raid;
</programlisting>
</para>
<para>
Change the owner of tablespace <literal>index_space</literal>:
<programlisting>
ALTER TABLESPACE index_space OWNER TO mary;
</programlisting></para>
</refsect1>
<refsect1>
<title>Compatibility</title>
<para>
There is no <command>ALTER TABLESPACE</command> statement in
the SQL standard.
</para>
</refsect1>
<refsect1>
<title>See Also</title>
<simplelist type="inline">
<member><xref linkend="sql-createtablespace"/></member>
<member><xref linkend="sql-droptablespace"/></member>
</simplelist>
</refsect1>
</refentry>