psql-ref.sgml

PostgreSQL7.4.6 for Linux

        wherever the <command>COPY</command> itself came from (for
        example, a script run with the <option>-f</option> option), and
        <literal>stdout</literal> refers to the query output stream (see
        <command>\o</command> meta-command below).
        </para>
        </note>
        </listitem>
      </varlistentry>

      <varlistentry>
        <term><literal>\copyright</literal></term>
        <listitem>
        <para>
        Shows the copyright and distribution terms of
        <application>PostgreSQL</application>.
        </para>
        </listitem>
      </varlistentry>

      <varlistentry>
        <term><literal>\d</literal> [ <replaceable class="parameter">pattern</replaceable> ]</term>

        <listitem>
        <para>
	For each relation (table, view, index, or sequence) matching the
	<replaceable class="parameter">pattern</replaceable>, show all
	columns, their types, and any special
	attributes such as <literal>NOT NULL</literal> or defaults, if
	any. Associated indexes, constraints, rules, and triggers are
	also shown, as is the view definition if the relation is a view.
	(<quote>Matching the pattern</> is defined below.)
	</para>

	<para>
	The command form <literal>\d+</literal> is identical, but any
	comments associated with the table columns are shown as well.
	</para>

	<note>
	<para>
	If <command>\d</command> is used without a
	<replaceable class="parameter">pattern</replaceable> argument, it is
	equivalent to <command>\dtvs</command> which will show a list of
	all tables, views, and sequences. This is purely a convenience
	measure.
	</para>
	</note>
	</listitem>
      </varlistentry>

      <varlistentry>
        <term><literal>\da</literal> [ <replaceable class="parameter">pattern</replaceable> ]</term>

        <listitem>
        <para>
        Lists all available aggregate functions, together with the data
        type they operate on. If <replaceable
        class="parameter">pattern</replaceable>
        is specified, only aggregates whose names match the pattern are shown.
        </para>
        </listitem>
      </varlistentry>


      <varlistentry>
        <term><literal>\dc</literal> [ <replaceable class="parameter">pattern</replaceable> ]</term>
        <listitem>
        <para>
        Lists all available conversions between character-set encodings.
	If <replaceable class="parameter">pattern</replaceable>
        is specified, only conversions whose names match the pattern are
	listed.
        </para>
        </listitem>
      </varlistentry>


      <varlistentry>
        <term><literal>\dC</literal></term>
        <listitem>
        <para>
        Lists all available type casts.
        </para>
        </listitem>
      </varlistentry>


      <varlistentry>
        <term><literal>\dd</literal> [ <replaceable class="parameter">pattern</replaceable> ]</term>
        <listitem>
        <para>
        Shows the descriptions of objects matching the <replaceable
        class="parameter">pattern</replaceable>, or of all visible objects if
	no argument is given.  But in either case, only objects that have
	a description are listed.
        (<quote>Object</quote> covers aggregates, functions, operators,
        types, relations (tables, views, indexes, sequences, large
        objects), rules, and triggers.) For example:
<programlisting>
=> <userinput>\dd version</userinput>
                     Object descriptions
   Schema   |  Name   |  Object  |        Description
------------+---------+----------+---------------------------
 pg_catalog | version | function | PostgreSQL version string
(1 row)
</programlisting>
        </para>

        <para>
        Descriptions for objects can be created with the
        <command>COMMENT</command> <acronym>SQL</acronym> command.
	</para>
        </listitem>
      </varlistentry>


      <varlistentry>
        <term><literal>\dD</literal> [ <replaceable class="parameter">pattern</replaceable> ]</term>
        <listitem>
        <para>
        Lists all available domains. If <replaceable
        class="parameter">pattern</replaceable>
        is specified, only matching domains are shown.
        </para>
        </listitem>
      </varlistentry>


      <varlistentry>
        <term><literal>\df [ <replaceable class="parameter">pattern</replaceable> ]</literal></term>

        <listitem>
        <para>
        Lists available functions, together with their argument and
        return types. If <replaceable
        class="parameter">pattern</replaceable>
        is specified, only functions whose names match the pattern are shown.
	If the form
        <literal>\df+</literal> is used, additional information about
        each function, including language and description, is shown.
        </para>

        <note>
        <para>
        To reduce clutter, <literal>\df</> does not show data type I/O
	functions.  This is implemented by ignoring functions that accept
	or return type <type>cstring</>.
        </para>
        </note>

        </listitem>
      </varlistentry>


      <varlistentry>
        <term><literal>\distvS [ <replaceable class="parameter">pattern</replaceable> ]</literal></term>

	<listitem>
	<para>
	This is not the actual command name: the letters i, s, t, v, S
	stand for index, sequence, table, view, and system table,
	respectively. You can specify any or all of these letters, in any
	order, to obtain a listing of all the matching objects.  The letter
	S restricts the listing to system objects; without S, only non-system
	objects are shown.
	If <literal>+</literal> is appended to the command name, each object is
	listed with its associated description, if any.
	</para>

	<para>
	If <replaceable class="parameter">pattern</replaceable> is
	specified, only objects whose names match the pattern are listed.
	</para>
	</listitem>
      </varlistentry>


      <varlistentry>
        <term><literal>\dl</literal></term>
	<listitem>
	<para>
	This is an alias for <command>\lo_list</command>, which shows a
	list of large objects.
	</para>
	</listitem>
      </varlistentry>


      <varlistentry>
        <term><literal>\dn</literal> [ <replaceable class="parameter">pattern</replaceable> ]</term>

        <listitem>
        <para>
        Lists all available schemas (namespaces). If <replaceable
        class="parameter">pattern</replaceable> (a regular expression)
        is specified, only schemas whose names match the pattern are listed.
        </para>
        </listitem>
      </varlistentry>


      <varlistentry>
        <term><literal>\do [ <replaceable class="parameter">pattern</replaceable> ]</literal></term>
        <listitem>
        <para>
        Lists available operators with their operand and return types.
	If <replaceable class="parameter">pattern</replaceable> is
	specified, only operators whose names match the pattern are listed.
        </para>
        </listitem>
      </varlistentry>


      <varlistentry>
        <term><literal>\dp</literal> [ <replaceable class="parameter">pattern</replaceable> ]</term>
	<listitem>
	<para>
        Produces a list of all available tables with their
        associated access privileges.
	If <replaceable class="parameter">pattern</replaceable> is
	specified, only tables whose names match the pattern are listed.
	</para>

	<para>
	The commands <xref linkend="SQL-GRANT"> and
	<xref linkend="SQL-REVOKE">
	are used to set access privileges.  See <xref linkend="SQL-GRANT">
	for more information.
	</para>
	</listitem>
      </varlistentry>


      <varlistentry>
        <term><literal>\dT [ <replaceable class="parameter">pattern</replaceable> ]</literal></term>
        <listitem>
        <para>
        Lists all data types or only those that match <replaceable
        class="parameter">pattern</replaceable>. The command form
        <literal>\dT+</literal> shows extra information.
        </para>
        </listitem>
      </varlistentry>


      <varlistentry>
        <term><literal>\du [ <replaceable class="parameter">pattern</replaceable> ]</literal></term>
        <listitem>
        <para>
        Lists all database users or only those that match <replaceable
        class="parameter">pattern</replaceable>.
        </para>
        </listitem>
      </varlistentry>


      <varlistentry>
        <term><literal>\edit</literal> (or <literal>\e</literal>) [ <replaceable class="parameter">filename</replaceable> ]</term>

        <listitem>
        <para>
        If <replaceable class="parameter">filename</replaceable> is
        specified, the file is edited; after the editor exits, its
        content is copied back to the query buffer. If no argument is
        given, the current query buffer is copied to a temporary file
        which is then edited in the same fashion.
        </para>

        <para>
        The new query buffer is then re-parsed according to the normal
        rules of <application>psql</application>, where the whole buffer
        is treated as a single line. (Thus you cannot make scripts this
        way. Use <command>\i</command> for that.) This means also that
        if the query ends with (or rather contains) a semicolon, it is
        immediately executed. In other cases it will merely wait in the
        query buffer.
        </para>

        <tip>
        <para>
        <application>psql</application> searches the environment
        variables <envar>PSQL_EDITOR</envar>, <envar>EDITOR</envar>, and
        <envar>VISUAL</envar> (in that order) for an editor to use. If
        all of them are unset, <filename>/bin/vi</filename> is run.
        </para>
        </tip>
        </listitem>
      </varlistentry>


      <varlistentry>
        <term><literal>\echo</literal> <replaceable class="parameter">text</replaceable> [ ... ]</term>
        <listitem>
	<para>
        Prints the arguments to the standard output, separated by one
        space and followed by a newline. This can be useful to
        intersperse information in the output of scripts. For example:
<programlisting>
=> <userinput>\echo `date`</userinput>
Tue Oct 26 21:40:57 CEST 1999
</programlisting>
        If the first argument is an unquoted <literal>-n</literal> the the trailing
        newline is not written.
	</para>

	<tip>
	<para>
	If you use the <command>\o</command> command to redirect your
	query output you may wish to use <command>\qecho</command>
	instead of this command.
	</para>
	</tip>
	</listitem>
      </varlistentry>


      <varlistentry>
        <term><literal>\encoding</literal> [ <replaceable class="parameter">encoding</replaceable> ]</term>

        <listitem>
        <para>
        Sets the client character set encoding.  Without an argument, this command
        shows the current encoding.
        </para>
        </listitem>
      </varlistentry>


      <varlistentry>
        <term><literal>\f</literal> [ <replaceable class="parameter">string</replaceable> ]</term>

        <listitem>
        <para>
        Sets the field separator for unaligned query output. The default
        is the vertical bar (<literal>|</literal>). See also
        <command>\pset</command> for a generic way of setting output
        options.
        </para>
        </listitem>
      </varlistentry>


      <varlistentry>
        <term><literal>\g</literal> [ { <replaceable class="parameter">filename</replaceable> | <literal>|</literal><replaceable class="parameter">command</replaceable> } ]</term>

        <listitem>
        <para>
        Sends the current query input buffer to the server and
        optionally saves the output in <replaceable
        class="parameter">filename</replaceable> or pipes the output
        into a separate Unix shell to execute <replaceable
        class="parameter">command</replaceable>. A bare
        <literal>\g</literal> is virtually equivalent to a semicolon. A
        <literal>\g</literal> with argument is a <quote>one-shot</quote>
        alternative to the <command>\o</command> command.
        </para>
        </listitem>
      </varlistentry>

      <varlistentry>
        <term><literal>\help</literal> (or <literal>\h</literal>) [ <replaceable class="parameter">command</replaceable> ]</term>
        <listitem>
        <para>
        Gives syntax help on the specified <acronym>SQL</acronym>
        command. If <replaceable class="parameter">command</replaceable>
        is not specified, then <application>psql</application> will list
        all the commands for which syntax help is available. If
        <replaceable class="parameter">command</replaceable> is an
        asterisk (<literal>*</literal>), then syntax help on all
        <acronym>SQL</acronym> commands is shown.
        </para>

	<note>
	<para>
	To simplify typing, commands that consists of several words do
	not have to be quoted. Thus it is fine to type <userinput>\help