<REFENTRY ID="APP-PSQL">
<REFMETA>
<REFENTRYTITLE>
<application>psql</application>
</REFENTRYTITLE>
<REFMISCINFO>Application</REFMISCINFO>
</REFMETA>
<REFNAMEDIV>
<REFNAME id="psql-ref">
<application>psql</application>
</REFNAME>
<REFPURPOSE>
<productname>Postgres</productname> interactive client
</REFPURPOSE>
<REFSYNOPSISDIV>
<REFSYNOPSISDIVINFO>
<DATE>1998-09-26</DATE>
</REFSYNOPSISDIVINFO>
<SYNOPSIS>
psql [ <replaceable class="parameter">dbname</replaceable> ]
psql -A [ -c <replaceable class="parameter">query</replaceable> ] [ -d <replaceable class="parameter">dbname</replaceable> ]
    -e [ -f <replaceable class="parameter">filename</replaceable> ] [ -F <replaceable class="parameter">separator</replaceable> ] [ -h <replaceable class="parameter">hostname</replaceable> ] -Hln
    [ -o <replaceable class="parameter">filename</replaceable> ] [ -p <replaceable class="parameter">port</replaceable> ] -qsSt ] [ -T <replaceable class="parameter">table_options</replaceable> ] -ux [ <replaceable class="parameter">dbname</replaceable> ]
</SYNOPSIS>

<REFSECT2 ID="R2-APP-PSQL-1">
<REFSECT2INFO>
<DATE>1998-09-26</DATE>
</REFSECT2INFO>
<TITLE>
Inputs
</TITLE>
<PARA>
<application>psql</application> accepts many command-line arguments,
a rich set of meta-commands, and the full <acronym>SQL</acronym> language
supported by <productname>Postgres</productname>. The most common
command-line arguments are:

<VARIABLELIST>
<VARLISTENTRY>
<TERM>
<REPLACEABLE CLASS="PARAMETER">dbname</REPLACEABLE>
</TERM>
<LISTITEM>
<PARA>
The name of an existing database to access.
<replaceable class="parameter">dbname</replaceable>
defaults to the value of the
<envar>USER</envar>
environment variable or, if that's not set, to the Unix account name of the
current user.

</PARA>
</LISTITEM>
</VARLISTENTRY>

<VARLISTENTRY>
<TERM>
-c <replaceable class="parameter">query</replaceable>
</TERM>
<LISTITEM>
<PARA>
A single query to run. <application>psql</application> will exit on completion.
</PARA>
</LISTITEM>
</VARLISTENTRY>

</variablelist>

<para>
The full set of command-line arguments and meta-commands are described in a following
section.

<para>
There are some environment variables which can be used in liu of
command line arguments. 
Additionally, the <productname>Postgres</productname> frontend library used by 
the <application>psql</application> application
looks for other optional environment variables to configure, for example,
the style of date/time representation and the local time zone. Refer
to the chapter on <filename>libpq</filename> in the
<citetitle>Programmer's Guide</citetitle> for more details.

<para>
You may set any of the following environment variables to avoid
specifying command-line options:

<VARIABLELIST>
<VARLISTENTRY>
<TERM>
<envar>PGHOST</envar>
</TERM>
<LISTITEM>
<PARA>
The <acronym>DNS</acronym> host name of the database server.
Setting <envar>PGHOST</envar> to a non-zero-length string causes
<acronym>TCP/IP</acronym> communication
to be used, rather than the default local Unix domain sockets.
</PARA>
</LISTITEM>
</VARLISTENTRY>

<VARLISTENTRY>
<TERM>
<envar>PGPORT</envar>
</TERM>
<LISTITEM>
<PARA>
</PARA>
</LISTITEM>
</VARLISTENTRY>

<VARLISTENTRY>
<TERM>
<envar>PGTTY</envar>
</TERM>
<LISTITEM>
<PARA>
</PARA>
</LISTITEM>
</VARLISTENTRY>

<VARLISTENTRY>
<TERM>
<envar>PGOPTION</envar>
</TERM>
<LISTITEM>
<PARA>
If <envar>PGOPTION</envar>
is specified, then the options it contains are parsed
.BR before
any command-line options.
</PARA>
</LISTITEM>
</VARLISTENTRY>

<VARLISTENTRY>
<TERM>
<envar>PGREALM</envar>
</TERM>
<LISTITEM>
<PARA>
<envar>PGREALM</envar>
only applies if
<productname>Kerberos</productname>
authentication is in use.  
If this environment variable is set, <productname>Postgres</productname>
will attempt authentication with servers for this realm and will use
separate ticket files to avoid conflicts with local ticket files.
See the <citetitle>PostgreSQL Administrator's Guide</citetitle>
for additional information on
<productname>Kerberos</productname>.

</variablelist>

<REFSECT2 ID="R2-APP-PSQL-2">
<REFSECT2INFO>
<DATE>1998-09-26</DATE>
</REFSECT2INFO>
<TITLE>
Outputs
</TITLE>
<PARA>

<application>psql</application>
returns 0 to the shell on successful completion of all queries,
1 for errors, 2 for abrupt disconnection from the backend.
<application>psql</application>
will also return 1 if the connection to a database could not be made for
any reason.

<REFSECT1 ID="R1-APP-PSQL-1">
<REFSECT1INFO>
<DATE>1998-09-26</DATE>
</REFSECT1INFO>
<TITLE>
Description
</TITLE>
<PARA>
<application>psql</application> is a character-based front-end to 
<productname>Postgres</productname>.
It enables you to
type in queries interactively, issue them to <productname>Postgres</productname>, 
and see the query
results.

<para>
<application>psql</application>
is a <productname>Postgres</productname> client application.  Hence, a
<application>postmaster</application> process
 must be running on the database server host before
<application>psql</application>
is executed.  In addition, the correct parameters to identify
the database server, such as the
<application>postmaster</application> host name,
 may need to be specified
as described below.

<para>
When
<application>psql</application>
starts, it reads SQL commands from
<filename>/etc/psqlrc</filename>
and then from
<filename>$(<envar>HOME</envar>)/.psqlrc</filename>
This allows SQL commands like
<command>SET</command>
which can be used to set the date style to be run at the start of
every session.

<REFSECT2 ID="R2-APP-PSQL-3">
<REFSECT2INFO>
<DATE>1998-09-26</DATE>
</REFSECT2INFO>
<TITLE>
Connecting To A Database
</TITLE>
<para>
<application>psql</application>
attempts to make a connection to the database at the hostname and
port number specified on the command line.   If the connection could not
be made for any reason (e.g. insufficient privileges, postmaster is not
running on the server, etc)
.IR <application>psql</application>
will return an error that says
<programlisting>
Connection to database failed.
</programlisting>
The reason for the connection failure is not provided.

<REFSECT2 ID="R2-APP-PSQL-4">
<REFSECT2INFO>
<DATE>1998-09-26</DATE>
</REFSECT2INFO>
<TITLE>
Entering Queries
</TITLE>
<para>
In normal operation, 
<application>psql</application> provides a prompt with the name of the
database that <application>psql</application> is current connected to 
followed by the string "=>".
For example,
<programlisting>
$ <userinput>psql testdb</userinput>
Welcome to the POSTGRESQL interactive sql monitor:
  Please read the file COPYRIGHT for copyright terms of POSTGRESQL

   type \e? for help on slash commands
   type \eq to quit
   type \eg or terminate with semicolon to execute query
 You are currently connected to the database: testdb

testdb=>
</programlisting>

<para>
At the prompt, the user may type in <acronym>SQL</acronym> queries.  
Unless the -S option
is set, input lines are sent to the backend when a query-terminating
semicolon is reached.

<para>
Whenever a query is executed, 
<application>psql</application> also polls for asynchronous notification
events generated by <command>LISTEN</command> and <command>NOTIFY</command>.

<para>
<application>psql</application>
can be used in a pipe sequence, and automatically detects when it
is not listening or talking to a real tty.

<REFSECT1 ID="R1-APP-PSQL-2">
<REFSECT1INFO>
<DATE>1998-09-26</DATE>
</REFSECT1INFO>
<TITLE>
Command-line Options
</TITLE>
<para>
<application>psql</application>
understands the following command-line options:

<VARIABLELIST>
<VARLISTENTRY>
<TERM>
-A
</TERM>
<LISTITEM>
<PARA>
Turn off fill justification when printing out table elements.

<VARLISTENTRY>
<TERM>
-c <replaceable class="parameter">query</replaceable>
</TERM>
<LISTITEM>
<PARA>
Specifies that
<application>psql</application>
is to execute one query string,
<replaceable class="parameter">query</replaceable>,
and then exit.  This is useful for shell scripts, typically in
conjunction with the <option>-q</option> option in shell scripts.

<VARLISTENTRY>
<TERM>
-d <replaceable class="parameter">dbname</replaceable>
</TERM>
<LISTITEM>
<PARA>
Specifies the name of the database to connect to. This is equivalent to specifying
<replaceable class="parameter">dbname</replaceable> as the last field in the
command line.

<VARLISTENTRY>
<TERM>
-e
</TERM>
<LISTITEM>
<PARA>
Echo the query sent to the backend

<VARLISTENTRY>
<TERM>
-f <replaceable class="parameter">filename</replaceable>
</TERM>
<LISTITEM>
<PARA>
Use the file <replaceable class="parameter">filename</replaceable>
as the source of queries instead of reading queries interactively.
This file must be specified for and visible to the client frontend.

<VARLISTENTRY>
<TERM>
-F <replaceable class="parameter">separator</replaceable>
</TERM>
<LISTITEM>
<PARA>
Use <replaceable class="parameter">separator</replaceable>
as the field separator.
The default is an ASCII vertical bar ("|").

<VARLISTENTRY>
<TERM>
-h <replaceable class="parameter">hostname</replaceable>
</TERM>
<LISTITEM>
<PARA>
Specifies the host name of the machine on which the
<application>postmaster</application>
is running.
Without this option, communication is performed using
local Unix domain sockets.

<VARLISTENTRY>
<TERM>
-H
</TERM>
<LISTITEM>
<PARA>
Turns on
<acronym>HTML 3.0</acronym>
tabular output.

<VARLISTENTRY>
<TERM>
-l
</TERM>
<LISTITEM>
<PARA>
Lists all available databases, then exit. Other non-connection options are ignored.

<VARLISTENTRY>
<TERM>
-n
</TERM>
<LISTITEM>
<PARA>
Do not use the readline library for input line editing and command history.

<VARLISTENTRY>
<TERM>
-o <replaceable class="parameter">filename</replaceable>
</TERM>
<LISTITEM>
<PARA>
Put all output into file <replaceable class="parameter">filename</replaceable>.
The path must be writable by the client.

<VARLISTENTRY>
<TERM>
-p <replaceable class="parameter">port</replaceable>
</TERM>
<LISTITEM>
<PARA>
Specifies the TCP/IP port or, by omission, the local Unix domain socket file
extension on which the
<application>postmaster</application>
is listening for connections.  Defaults to the value of the
<envar>PGPORT</envar>
environment variable, if set, or to 5432.

<VARLISTENTRY>
<TERM>
-q
</TERM>
<LISTITEM>
<PARA>
Specifies that
<application>psql</application>
should do its work quietly.  By default, it
prints welcome and exit messages and prompts for each query, and prints
out the number of rows returned from a query.
If this option is used, none of this happens. This is useful with the
<option>-c</option> option.

<VARLISTENTRY>
<TERM>
-s
</TERM>
<LISTITEM>
<PARA>
Run in single-step mode where the user is prompted for each query before
it is sent to the backend.

<VARLISTENTRY>
<TERM>
-S
</TERM>
<LISTITEM>
<PARA>
Runs in single-line mode where each query is terminated by a newline,
instead of a semicolon.

<VARLISTENTRY>
<TERM>
-t
</TERM>
<LISTITEM>
<PARA>
Turn off printing of column names.
This is useful with the
<option>-c</option>
option in shell scripts.

<VARLISTENTRY>
<TERM>
-T <replaceable class="parameter">table_options</replaceable>
</TERM>
<LISTITEM>
<PARA>
Allows you to specify options to be placed within the
 <sgmltag>table ...</sgmltag> tag for <acronym>HTML 3.0</acronym>
tabular output.For example, <literal>border</literal>
will give you tables with borders.
This must be used in conjunction with the <option>-H</option> option.

<VARLISTENTRY>
<TERM>
-u
</TERM>
<LISTITEM>
<PARA>
Asks the user for the user name and password before connecting to the database.
If the database does not require password authentication then these are
ignored.  If the option is not used (and the PGPASSWORD environment variable
is not set) and the database requires password authentication, then the
connection will fail.  The user name is ignored anyway.

<VARLISTENTRY>
<TERM>
-x
</TERM>
<LISTITEM>
<PARA>
Turns on extended row format mode. When enabled each row will have its column
names printed on the left with the column values printed on the right.
This is useful for rows which are otherwise too long to fit into
one screen line. HTML row output supports this mode also.
</variablelist>

<para>
You may set environment variables to avoid typing some of the above
options.  See the section on environment variables below.


<REFSECT1 ID="R1-APP-PSQL-3">
<REFSECT1INFO>
<DATE>1998-09-26</DATE>
</REFSECT1INFO>
<TITLE>
<application>psql</application> Meta-Commands
</TITLE>
<para>
Anything you enter in <application>psql</application> 
that begins with an unquoted backslash is a <application>psql</application>
meta-command.  Anything else is <acronym>SQL</acronym>
 and simply goes into the current query buffer
(and once you have at least one complete query, it gets automatically 
submitted to the backend).  
<Application>psql</Application> meta-commands are also called slash commands.

<para>
The format of a <application>psql</application> command is the backslash, 
followed immediately by
a command verb, then any arguments.  The arguments are separated from the
command verb and each other by any number of white space characters.

<para>
With single character command verbs, you don't actually need to separate the
command verb from the argument with white space, for historical reasons.
You should anyway.

<para>
The following meta-commands are defined:

<VARIABLELIST>
<VARLISTENTRY>
<TERM>
<literal>\a</literal>
</TERM>
<LISTITEM>
<PARA>
Toggle field alignment when printing out table elements.

<VARLISTENTRY>
<TERM>
<literal>\C</literal> <replaceable class="parameter">caption</replaceable>
</TERM>
<LISTITEM>
<PARA>
Set the HTML3.0 table caption to 
<quote><replaceable class="parameter">caption</replaceable></quote>.

<VARLISTENTRY>
<TERM>
<literal>\connect</literal> <replaceable class="parameter">dbname</replaceable> [ <replaceable class="parameter">username</replaceable> ]
</TERM>
<LISTITEM>
<PARA>
Establish a connection to a new database, using the default 
<replaceable class="parameter">username</replaceable> if none is specified.
The previous connection is closed.

<VARLISTENTRY>
<TERM>
<literal>\copy</literal> <replaceable class="parameter">dbname</replaceable> { FROM | TO } <replaceable class="parameter">filename</replaceable>
</TERM>
<LISTITEM>
<PARA>
Perform a frontend (client) copy.  This is an operation that runs a SQL COPY command,
but instead of the backend reading or writing the specified file, and 
consequently requiring backend access and special user privilege, 
<application>psql</application> reads or writes the 
file and routes the data to or from the backend.  The default <literal>tab</literal>
delimiter is used.
<tip>
<para>
This operation is not as efficient as the <acronym>SQL</acronym> 
<command>COPY</command> command because all data must pass through the
client/server IP or socket connection. For large amounts of data this other
technique may be preferable.
</tip>

<VARLISTENTRY>
<TERM>
<literal>\d</literal> [ <replaceable class="parameter">table</replaceable> ]
</TERM>
<LISTITEM>
<PARA>
List tables in the database, or if <replaceable class="parameter">table</replaceable>
is specified, list the columns in that table.
If table name is specified as an asterisk (<quote>*</quote>),
list all tables and column information for each tables.

<VARLISTENTRY>
<TERM>
<literal>\da</literal>
</TERM>
<LISTITEM>
<PARA>
List all available aggregates.

<VARLISTENTRY>
<TERM>
<literal>\dd</literal> <replaceable class="parameter">object</replaceable>
</TERM>
<LISTITEM>
<PARA>
List the description from <literal>pg_description</literal>
of the specified object, which can be a
table, table.column, type, operator, or aggregate.
<tip>
<para>
Not all objects have a description in <literal>pg_description</literal>.
This meta-command can be useful to get a quick description of a native
<productname>Postgres</productname> feature.
</tip>

<VARLISTENTRY>
<TERM>
<literal>\df</literal>
</TERM>
<LISTITEM>
<PARA>
List functions.

<VARLISTENTRY>
<TERM>
<literal>\di</literal>
</TERM>
<LISTITEM>
<PARA>
List only indexes.

<VARLISTENTRY>
<TERM>
<literal>\do</literal>
</TERM>
<LISTITEM>
<PARA>
List only operators.

<VARLISTENTRY>
<TERM>
<literal>\ds</literal>
</TERM>
<LISTITEM>
<PARA>
List only sequences.

<VARLISTENTRY>
<TERM>
<literal>\dS</literal>
</TERM>
<LISTITEM>
<PARA>
List system tables and indexes.

<VARLISTENTRY>
<TERM>
<literal>\dt</literal>
</TERM>
<LISTITEM>
<PARA>
List only non-system tables.

<VARLISTENTRY>
<TERM>
<literal>\dT</literal>
</TERM>
<LISTITEM>
<PARA>
List types.

<VARLISTENTRY>
<TERM>
<literal>\e</literal> [ <replaceable class="parameter">filename</replaceable> ]
</TERM>
<LISTITEM>
<PARA>
Edit the current query buffer or the contents of the file
<replaceable class="parameter">filename</replaceable>.

<VARLISTENTRY>
<TERM>
<literal>\E</literal> [ <replaceable class="parameter">filename</replaceable> ]
</TERM>
<LISTITEM>
<PARA>
Edit the current query buffer or the contents of the file
<replaceable class="parameter">filename</replaceable>
and execute it upon editor exit.

<VARLISTENTRY>
<TERM>
<literal>\f</literal> [ <replaceable class="parameter">separator</replaceable> ]
</TERM>
<LISTITEM>
<PARA>
Set the field separator.  Default is a single blank space.

<VARLISTENTRY>
<TERM>
<literal>\g</literal> [ { <replaceable class="parameter">filename</replaceable> | <literal>|</literal><replaceable class="parameter">command</replaceable> } ]
</TERM>
<LISTITEM>
<PARA>
Send the current query input buffer to the backend and optionally
save the output in <replaceable class="parameter">filename</replaceable>
or pipe the output into a separate Unix shell to execute
<replaceable class="parameter">command</replaceable>.

<VARLISTENTRY>
<TERM>
<literal>\h</literal> [ <replaceable class="parameter">command</replaceable> ]
</TERM>
<LISTITEM>
<PARA>
Give syntax help on the specified SQL command.  
If <replaceable class="parameter">command</replaceable> is not a defined SQL command
(or is not documented in <application>psql</application>), or 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 (<quote>*</quote>), then
give syntax help on all SQL commands.

<VARLISTENTRY>
<TERM>
<literal>\H</literal>
</TERM>
<LISTITEM>
<PARA>
Toggle <acronym>HTML3</acronym> output. This is equivalent to the <option>-H</option>
command-line option.

<VARLISTENTRY>
<TERM>
<literal>\i</literal> <replaceable class="parameter">filename</replaceable>
</TERM>
<LISTITEM>
<PARA>
Read queries from the file <replaceable class="parameter">filename</replaceable>
into the query input buffer.

<VARLISTENTRY>
<TERM>
<literal>\l</literal>
</TERM>
<LISTITEM>
<PARA>
List all the databases in the server.

<VARLISTENTRY>
<TERM>
<literal>\m</literal>
</TERM>
<LISTITEM>
<PARA>
Toggle the old monitor-like table display, which includes border characters
surrounding the table.
This is standard SQL output.
By default, <application>psql</application> includes only field separators
between columns.

<VARLISTENTRY>
<TERM>
<literal>\o</literal> [ { <replaceable class="parameter">filename</replaceable> | <literal>|</literal><replaceable class="parameter">command</replaceable> } ]
</TERM>
<LISTITEM>
<PARA>
Save future query results to the file
<replaceable class="parameter">filename</replaceable> or pipe future
results into a separate Unix shell to execute
<replaceable class="parameter">command</replaceable>.
If no arguments are specified, send query results to
<filename>stdout</filename>.

<VARLISTENTRY>
<TERM>
<literal>\p</literal>
</TERM>
<LISTITEM>
<PARA>
Print the current query buffer.

<VARLISTENTRY>
<TERM>
<literal>\q</literal>
</TERM>
<LISTITEM>
<PARA>
Quit the <application>psql</application> program.

<VARLISTENTRY>
<TERM>
<literal>\r</literal>
</TERM>
<LISTITEM>
<PARA>
Reset(clear) the query buffer.

<VARLISTENTRY>
<TERM>
<literal>\s</literal> [ <replaceable class="parameter">filename</replaceable> ]
</TERM>
<LISTITEM>
<PARA>
Print or save the command line history to 
<replaceable class="parameter">filename</replaceable>.
If <replaceable class="parameter">filename</replaceable> is omitted,
do not save subsequent commands to a history file.
This option is only available if <application>psql</application> is
configured to use readline.

<VARLISTENTRY>
<TERM>
<literal>\t</literal>
</TERM>
<LISTITEM>
<PARA>
Toggle display of output column name headings and row count footer (defaults to on).

<VARLISTENTRY>
<TERM>
<literal>\T</literal> <replaceable class="parameter">table_options</replaceable>
</TERM>
<LISTITEM>
<PARA>
Allows you to specify options to be placed within the
 <sgmltag>table ...</sgmltag> tag
for <acronym>HTML 3.0</acronym>
tabular output.For example, <literal>border</literal>
will give you tables with borders.
This must be used in conjunction with the <command>\H</command> meta-command.

<VARLISTENTRY>
<TERM>
<literal>\x</literal>
</TERM>
<LISTITEM>
<PARA>
Toggles extended row format mode. When enabled each row will have its column
names printed on the left with the column values printed on the right.
This is useful for rows which are otherwise too long to fit into
one screen line. <acronym>HTML</acronym> row output mode supports this flag too.

<VARLISTENTRY>
<TERM>
<literal>\w</literal> <replaceable class="parameter">filename</replaceable>
</TERM>
<LISTITEM>
<PARA>
Outputs the current query buffer to the file
<replaceable class="parameter">filename</replaceable>.

<VARLISTENTRY>
<TERM>
<literal>\z</literal>
</TERM>
<LISTITEM>
<PARA>
Produces a list of all tables in the database with their appropriate ACLs
(grant/revoke permissions) listed.

<VARLISTENTRY>
<TERM>
<literal>\!</literal> [ <replaceable class="parameter">command</replaceable> ]
</TERM>
<LISTITEM>
<PARA>
Escape to a separate Unix shell or execute the Unix command
<replaceable class="parameter">command</replaceable>.

<VARLISTENTRY>
<TERM>
<literal>\?</literal>
</TERM>
<LISTITEM>
<PARA>
Get help information about the slash (<quote>\</quote>) commands.

</variablelist>

</refentry>