Provided by: postgresql-client-12_12.20-0ubuntu0.20.04.1_amd64 
NAME
psql - PostgreSQL interactive terminal
SYNOPSIS
psql [option...] [dbname [username]]
DESCRIPTION
psql is a terminal-based front-end to PostgreSQL. It enables you to type in queries
interactively, issue them to PostgreSQL, and see the query results. Alternatively, input
can be from a file or from command line arguments. In addition, psql provides a number of
meta-commands and various shell-like features to facilitate writing scripts and automating
a wide variety of tasks.
OPTIONS
-a
--echo-all
Print all nonempty input lines to standard output as they are read. (This does not
apply to lines read interactively.) This is equivalent to setting the variable ECHO to
all.
-A
--no-align
Switches to unaligned output mode. (The default output mode is aligned.) This is
equivalent to \pset format unaligned.
-b
--echo-errors
Print failed SQL commands to standard error output. This is equivalent to setting the
variable ECHO to errors.
-c command
--command=command
Specifies that psql is to execute the given command string, command. This option can
be repeated and combined in any order with the -f option. When either -c or -f is
specified, psql does not read commands from standard input; instead it terminates
after processing all the -c and -f options in sequence.
command must be either a command string that is completely parsable by the server
(i.e., it contains no psql-specific features), or a single backslash command. Thus you
cannot mix SQL and psql meta-commands within a -c option. To achieve that, you could
use repeated -c options or pipe the string into psql, for example:
psql -c '\x' -c 'SELECT * FROM foo;'
or
echo '\x \\ SELECT * FROM foo;' | psql
(\\ is the separator meta-command.)
Each SQL command string passed to -c is sent to the server as a single request.
Because of this, the server executes it as a single transaction even if the string
contains multiple SQL commands, unless there are explicit BEGIN/COMMIT commands
included in the string to divide it into multiple transactions. (See Section 52.2.2.1
for more details about how the server handles multi-query strings.) Also, psql only
prints the result of the last SQL command in the string. This is different from the
behavior when the same string is read from a file or fed to psql's standard input,
because then psql sends each SQL command separately.
Because of this behavior, putting more than one SQL command in a single -c string
often has unexpected results. It's better to use repeated -c commands or feed multiple
commands to psql's standard input, either using echo as illustrated above, or via a
shell here-document, for example:
psql <<EOF
\x
SELECT * FROM foo;
EOF
--csv
Switches to CSV (Comma-Separated Values) output mode. This is equivalent to \pset
format csv.
-d dbname
--dbname=dbname
Specifies the name of the database to connect to. This is equivalent to specifying
dbname as the first non-option argument on the command line. The dbname can be a
connection string. If so, connection string parameters will override any conflicting
command line options.
-e
--echo-queries
Copy all SQL commands sent to the server to standard output as well. This is
equivalent to setting the variable ECHO to queries.
-E
--echo-hidden
Echo the actual queries generated by \d and other backslash commands. You can use this
to study psql's internal operations. This is equivalent to setting the variable
ECHO_HIDDEN to on.
-f filename
--file=filename
Read commands from the file filename, rather than standard input. This option can be
repeated and combined in any order with the -c option. When either -c or -f is
specified, psql does not read commands from standard input; instead it terminates
after processing all the -c and -f options in sequence. Except for that, this option
is largely equivalent to the meta-command \i.
If filename is - (hyphen), then standard input is read until an EOF indication or \q
meta-command. This can be used to intersperse interactive input with input from files.
Note however that Readline is not used in this case (much as if -n had been
specified).
Using this option is subtly different from writing psql < filename. In general, both
will do what you expect, but using -f enables some nice features such as error
messages with line numbers. There is also a slight chance that using this option will
reduce the start-up overhead. On the other hand, the variant using the shell's input
redirection is (in theory) guaranteed to yield exactly the same output you would have
received had you entered everything by hand.
-F separator
--field-separator=separator
Use separator as the field separator for unaligned output. This is equivalent to \pset
fieldsep or \f.
-h hostname
--host=hostname
Specifies the host name of the machine on which the server is running. If the value
begins with a slash, it is used as the directory for the Unix-domain socket.
-H
--html
Switches to HTML output mode. This is equivalent to \pset format html or the \H
command.
-l
--list
List all available databases, then exit. Other non-connection options are ignored.
This is similar to the meta-command \list.
When this option is used, psql will connect to the database postgres, unless a
different database is named on the command line (option -d or non-option argument,
possibly via a service entry, but not via an environment variable).
-L filename
--log-file=filename
Write all query output into file filename, in addition to the normal output
destination.
-n
--no-readline
Do not use Readline for line editing and do not use the command history. This can be
useful to turn off tab expansion when cutting and pasting.
-o filename
--output=filename
Put all query output into file filename. This is equivalent to the command \o.
-p port
--port=port
Specifies the TCP port or the local Unix-domain socket file extension on which the
server is listening for connections. Defaults to the value of the PGPORT environment
variable or, if not set, to the port specified at compile time, usually 5432.
-P assignment
--pset=assignment
Specifies printing options, in the style of \pset. Note that here you have to separate
name and value with an equal sign instead of a space. For example, to set the output
format to LaTeX, you could write -P format=latex.
-q
--quiet
Specifies that psql should do its work quietly. By default, it prints welcome messages
and various informational output. If this option is used, none of this happens. This
is useful with the -c option. This is equivalent to setting the variable QUIET to on.
-R separator
--record-separator=separator
Use separator as the record separator for unaligned output. This is equivalent to
\pset recordsep.
-s
--single-step
Run in single-step mode. That means the user is prompted before each command is sent
to the server, with the option to cancel execution as well. Use this to debug scripts.
-S
--single-line
Runs in single-line mode where a newline terminates an SQL command, as a semicolon
does.
Note
This mode is provided for those who insist on it, but you are not necessarily
encouraged to use it. In particular, if you mix SQL and meta-commands on a line
the order of execution might not always be clear to the inexperienced user.
-t
--tuples-only
Turn off printing of column names and result row count footers, etc. This is
equivalent to \t or \pset tuples_only.
-T table_options
--table-attr=table_options
Specifies options to be placed within the HTML table tag. See \pset tableattr for
details.
-U username
--username=username
Connect to the database as the user username instead of the default. (You must have
permission to do so, of course.)
-v assignment
--set=assignment
--variable=assignment
Perform a variable assignment, like the \set meta-command. Note that you must separate
name and value, if any, by an equal sign on the command line. To unset a variable,
leave off the equal sign. To set a variable with an empty value, use the equal sign
but leave off the value. These assignments are done during command line processing, so
variables that reflect connection state will get overwritten later.
-V
--version
Print the psql version and exit.
-w
--no-password
Never issue a password prompt. If the server requires password authentication and a
password is not available from other sources such as a .pgpass file, the connection
attempt will fail. This option can be useful in batch jobs and scripts where no user
is present to enter a password.
Note that this option will remain set for the entire session, and so it affects uses
of the meta-command \connect as well as the initial connection attempt.
-W
--password
Force psql to prompt for a password before connecting to a database, even if the
password will not be used.
If the server requires password authentication and a password is not available from
other sources such as a .pgpass file, psql will prompt for a password in any case.
However, psql will waste a connection attempt finding out that the server wants a
password. In some cases it is worth typing -W to avoid the extra connection attempt.
Note that this option will remain set for the entire session, and so it affects uses
of the meta-command \connect as well as the initial connection attempt.
-x
--expanded
Turn on the expanded table formatting mode. This is equivalent to \x or \pset
expanded.
-X
--no-psqlrc
Do not read the start-up file (neither the system-wide psqlrc file nor the user's
~/.psqlrc file).
-z
--field-separator-zero
Set the field separator for unaligned output to a zero byte. This is equivalent to
\pset fieldsep_zero.
-0
--record-separator-zero
Set the record separator for unaligned output to a zero byte. This is useful for
interfacing, for example, with xargs -0. This is equivalent to \pset recordsep_zero.
-1
--single-transaction
This option can only be used in combination with one or more -c and/or -f options. It
causes psql to issue a BEGIN command before the first such option and a COMMIT command
after the last one, thereby wrapping all the commands into a single transaction. This
ensures that either all the commands complete successfully, or no changes are applied.
If the commands themselves contain BEGIN, COMMIT, or ROLLBACK, this option will not
have the desired effects. Also, if an individual command cannot be executed inside a
transaction block, specifying this option will cause the whole transaction to fail.
-?
--help[=topic]
Show help about psql and exit. The optional topic parameter (defaulting to options)
selects which part of psql is explained: commands describes psql's backslash commands;
options describes the command-line options that can be passed to psql; and variables
shows help about psql configuration variables.
EXIT STATUS
psql returns 0 to the shell if it finished normally, 1 if a fatal error of its own occurs
(e.g., out of memory, file not found), 2 if the connection to the server went bad and the
session was not interactive, and 3 if an error occurred in a script and the variable
ON_ERROR_STOP was set.
USAGE
Connecting to a Database
psql is a regular PostgreSQL client application. In order to connect to a database you
need to know the name of your target database, the host name and port number of the
server, and what user name you want to connect as. psql can be told about those
parameters via command line options, namely -d, -h, -p, and -U respectively. If an
argument is found that does not belong to any option it will be interpreted as the
database name (or the user name, if the database name is already given). Not all of these
options are required; there are useful defaults. If you omit the host name, psql will
connect via a Unix-domain socket to a server on the local host, or via TCP/IP to localhost
on machines that don't have Unix-domain sockets. The default port number is determined at
compile time. Since the database server uses the same default, you will not have to
specify the port in most cases. The default user name is your operating-system user name,
as is the default database name. Note that you cannot just connect to any database under
any user name. Your database administrator should have informed you about your access
rights.
When the defaults aren't quite right, you can save yourself some typing by setting the
environment variables PGDATABASE, PGHOST, PGPORT and/or PGUSER to appropriate values. (For
additional environment variables, see Section 33.14.) It is also convenient to have a
~/.pgpass file to avoid regularly having to type in passwords. See Section 33.15 for more
information.
An alternative way to specify connection parameters is in a conninfo string or a URI,
which is used instead of a database name. This mechanism give you very wide control over
the connection. For example:
$ psql "service=myservice sslmode=require"
$ psql postgresql://dbmaster:5433/mydb?sslmode=require
This way you can also use LDAP for connection parameter lookup as described in
Section 33.17. See Section 33.1.2 for more information on all the available connection
options.
If the connection could not be made for any reason (e.g., insufficient privileges, server
is not running on the targeted host, etc.), psql will return an error and terminate.
If both standard input and standard output are a terminal, then psql sets the client
encoding to “auto”, which will detect the appropriate client encoding from the locale
settings (LC_CTYPE environment variable on Unix systems). If this doesn't work out as
expected, the client encoding can be overridden using the environment variable
PGCLIENTENCODING.
Entering SQL Commands
In normal operation, psql provides a prompt with the name of the database to which psql is
currently connected, followed by the string =>. For example:
$ psql testdb
psql (12.20)
Type "help" for help.
testdb=>
At the prompt, the user can type in SQL commands. Ordinarily, input lines are sent to the
server when a command-terminating semicolon is reached. An end of line does not terminate
a command. Thus commands can be spread over several lines for clarity. If the command was
sent and executed without error, the results of the command are displayed on the screen.
If untrusted users have access to a database that has not adopted a secure schema usage
pattern, begin your session by removing publicly-writable schemas from search_path. One
can add options=-csearch_path= to the connection string or issue SELECT
pg_catalog.set_config('search_path', '', false) before other SQL commands. This
consideration is not specific to psql; it applies to every interface for executing
arbitrary SQL commands.
Whenever a command is executed, psql also polls for asynchronous notification events
generated by LISTEN(7) and NOTIFY(7).
While C-style block comments are passed to the server for processing and removal,
SQL-standard comments are removed by psql.
Meta-Commands
Anything you enter in psql that begins with an unquoted backslash is a psql meta-command
that is processed by psql itself. These commands make psql more useful for administration
or scripting. Meta-commands are often called slash or backslash commands.
The format of a psql 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 whitespace characters.
To include whitespace in an argument you can quote it with single quotes. To include a
single quote in an argument, write two single quotes within single-quoted text. Anything
contained in single quotes is furthermore subject to C-like substitutions for \n (new
line), \t (tab), \b (backspace), \r (carriage return), \f (form feed), \digits (octal),
and \xdigits (hexadecimal). A backslash preceding any other character within single-quoted
text quotes that single character, whatever it is.
If an unquoted colon (:) followed by a psql variable name appears within an argument, it
is replaced by the variable's value, as described in SQL Interpolation. The forms
:'variable_name' and :"variable_name" described there work as well. The :{?variable_name}
syntax allows testing whether a variable is defined. It is substituted by TRUE or FALSE.
Escaping the colon with a backslash protects it from substitution.
Within an argument, text that is enclosed in backquotes (`) is taken as a command line
that is passed to the shell. The output of the command (with any trailing newline removed)
replaces the backquoted text. Within the text enclosed in backquotes, no special quoting
or other processing occurs, except that appearances of :variable_name where variable_name
is a psql variable name are replaced by the variable's value. Also, appearances of
:'variable_name' are replaced by the variable's value suitably quoted to become a single
shell command argument. (The latter form is almost always preferable, unless you are very
sure of what is in the variable.) Because carriage return and line feed characters cannot
be safely quoted on all platforms, the :'variable_name' form prints an error message and
does not substitute the variable value when such characters appear in the value.
Some commands take an SQL identifier (such as a table name) as argument. These arguments
follow the syntax rules of SQL: Unquoted letters are forced to lowercase, while double
quotes (") protect letters from case conversion and allow incorporation of whitespace into
the identifier. Within double quotes, paired double quotes reduce to a single double quote
in the resulting name. For example, FOO"BAR"BAZ is interpreted as fooBARbaz, and "A
weird"" name" becomes A weird" name.
Parsing for arguments stops at the end of the line, or when another unquoted backslash is
found. An unquoted backslash is taken as the beginning of a new meta-command. The special
sequence \\ (two backslashes) marks the end of arguments and continues parsing SQL
commands, if any. That way SQL and psql commands can be freely mixed on a line. But in any
case, the arguments of a meta-command cannot continue beyond the end of the line.
Many of the meta-commands act on the current query buffer. This is simply a buffer holding
whatever SQL command text has been typed but not yet sent to the server for execution.
This will include previous input lines as well as any text appearing before the
meta-command on the same line.
The following meta-commands are defined:
\a
If the current table output format is unaligned, it is switched to aligned. If it is
not unaligned, it is set to unaligned. This command is kept for backwards
compatibility. See \pset for a more general solution.
\c or \connect [ -reuse-previous=on|off ] [ dbname [ username ] [ host ] [ port ] |
conninfo ]
Establishes a new connection to a PostgreSQL server. The connection parameters to use
can be specified either using a positional syntax (one or more of database name, user,
host, and port), or using a conninfo connection string as detailed in Section 33.1.1.
If no arguments are given, a new connection is made using the same parameters as
before.
Specifying any of dbname, username, host or port as - is equivalent to omitting that
parameter.
The new connection can re-use connection parameters from the previous connection; not
only database name, user, host, and port, but other settings such as sslmode. By
default, parameters are re-used in the positional syntax, but not when a conninfo
string is given. Passing a first argument of -reuse-previous=on or -reuse-previous=off
overrides that default. If parameters are re-used, then any parameter not explicitly
specified as a positional parameter or in the conninfo string is taken from the
existing connection's parameters. An exception is that if the host setting is changed
from its previous value using the positional syntax, any hostaddr setting present in
the existing connection's parameters is dropped. Also, any password used for the
existing connection will be re-used only if the user, host, and port settings are not
changed. When the command neither specifies nor reuses a particular parameter, the
libpq default is used.
If the new connection is successfully made, the previous connection is closed. If the
connection attempt fails (wrong user name, access denied, etc.), the previous
connection will be kept if psql is in interactive mode. But when executing a
non-interactive script, processing will immediately stop with an error. This
distinction was chosen as a user convenience against typos on the one hand, and a
safety mechanism that scripts are not accidentally acting on the wrong database on the
other hand.
Examples:
=> \c mydb myuser host.dom 6432
=> \c service=foo
=> \c "host=localhost port=5432 dbname=mydb connect_timeout=10 sslmode=disable"
=> \c -reuse-previous=on sslmode=require -- changes only sslmode
=> \c postgresql://tom@localhost/mydb?application_name=myapp
\C [ title ]
Sets the title of any tables being printed as the result of a query or unset any such
title. This command is equivalent to \pset title title. (The name of this command
derives from “caption”, as it was previously only used to set the caption in an HTML
table.)
\cd [ directory ]
Changes the current working directory to directory. Without argument, changes to the
current user's home directory.
Tip
To print your current working directory, use \! pwd.
\conninfo
Outputs information about the current database connection.
\copy { table [ ( column_list ) ] } from { 'filename' | program 'command' | stdin | pstdin
} [ [ with ] ( option [, ...] ) ] [ where condition ]
\copy { table [ ( column_list ) ] | ( query ) } to { 'filename' | program 'command' |
stdout | pstdout } [ [ with ] ( option [, ...] ) ]
Performs a frontend (client) copy. This is an operation that runs an SQL COPY(7)
command, but instead of the server reading or writing the specified file, psql reads
or writes the file and routes the data between the server and the local file system.
This means that file accessibility and privileges are those of the local user, not the
server, and no SQL superuser privileges are required.
When program is specified, command is executed by psql and the data passed from or to
command is routed between the server and the client. Again, the execution privileges
are those of the local user, not the server, and no SQL superuser privileges are
required.
For \copy ... from stdin, data rows are read from the same source that issued the
command, continuing until \. is read or the stream reaches EOF. This option is useful
for populating tables in-line within a SQL script file. For \copy ... to stdout,
output is sent to the same place as psql command output, and the COPY count command
status is not printed (since it might be confused with a data row). To read/write
psql's standard input or output regardless of the current command source or \o option,
write from pstdin or to pstdout.
The syntax of this command is similar to that of the SQL COPY(7) command. All options
other than the data source/destination are as specified for COPY(7). Because of this,
special parsing rules apply to the \copy meta-command. Unlike most other
meta-commands, the entire remainder of the line is always taken to be the arguments of
\copy, and neither variable interpolation nor backquote expansion are performed in the
arguments.
Tip
Another way to obtain the same result as \copy ... to is to use the SQL COPY ...
TO STDOUT command and terminate it with \g filename or \g |program. Unlike \copy,
this method allows the command to span multiple lines; also, variable
interpolation and backquote expansion can be used.
Tip
These operations are not as efficient as the SQL COPY command with a file or
program data source or destination, because all data must pass through the
client/server connection. For large amounts of data the SQL command might be
preferable. Also, because of this pass-through method, \copy ... from in CSV mode
will erroneously treat a \. data value alone on a line as an end-of-input marker.
\copyright
Shows the copyright and distribution terms of PostgreSQL.
\crosstabview [ colV [ colH [ colD [ sortcolH ] ] ] ]
Executes the current query buffer (like \g) and shows the results in a crosstab grid.
The query must return at least three columns. The output column identified by colV
becomes a vertical header and the output column identified by colH becomes a
horizontal header. colD identifies the output column to display within the grid.
sortcolH identifies an optional sort column for the horizontal header.
Each column specification can be a column number (starting at 1) or a column name. The
usual SQL case folding and quoting rules apply to column names. If omitted, colV is
taken as column 1 and colH as column 2. colH must differ from colV. If colD is not
specified, then there must be exactly three columns in the query result, and the
column that is neither colV nor colH is taken to be colD.
The vertical header, displayed as the leftmost column, contains the values found in
column colV, in the same order as in the query results, but with duplicates removed.
The horizontal header, displayed as the first row, contains the values found in column
colH, with duplicates removed. By default, these appear in the same order as in the
query results. But if the optional sortcolH argument is given, it identifies a column
whose values must be integer numbers, and the values from colH will appear in the
horizontal header sorted according to the corresponding sortcolH values.
Inside the crosstab grid, for each distinct value x of colH and each distinct value y
of colV, the cell located at the intersection (x,y) contains the value of the colD
column in the query result row for which the value of colH is x and the value of colV
is y. If there is no such row, the cell is empty. If there are multiple such rows, an
error is reported.
\d[S+] [ pattern ]
For each relation (table, view, materialized view, index, sequence, or foreign table)
or composite type matching the pattern, show all columns, their types, the tablespace
(if not the default) and any special attributes such as NOT NULL or defaults.
Associated indexes, constraints, rules, and triggers are also shown. For foreign
tables, the associated foreign server is shown as well. (“Matching the pattern” is
defined in Patterns below.)
For some types of relation, \d shows additional information for each column: column
values for sequences, indexed expressions for indexes, and foreign data wrapper
options for foreign tables.
The command form \d+ is identical, except that more information is displayed: any
comments associated with the columns of the table are shown, as is the presence of
OIDs in the table, the view definition if the relation is a view, a non-default
replica identity setting.
By default, only user-created objects are shown; supply a pattern or the S modifier to
include system objects.
Note
If \d is used without a pattern argument, it is equivalent to \dtvmsE which will
show a list of all visible tables, views, materialized views, sequences and
foreign tables. This is purely a convenience measure.
\da[S] [ pattern ]
Lists aggregate functions, together with their return type and the data types they
operate on. If pattern is specified, only aggregates whose names match the pattern are
shown. By default, only user-created objects are shown; supply a pattern or the S
modifier to include system objects.
\dA[+] [ pattern ]
Lists access methods. If pattern is specified, only access methods whose names match
the pattern are shown. If + is appended to the command name, each access method is
listed with its associated handler function and description.
\db[+] [ pattern ]
Lists tablespaces. If pattern is specified, only tablespaces whose names match the
pattern are shown. If + is appended to the command name, each tablespace is listed
with its associated options, on-disk size, permissions and description.
\dc[S+] [ pattern ]
Lists conversions between character-set encodings. If pattern is specified, only
conversions whose names match the pattern are listed. By default, only user-created
objects are shown; supply a pattern or the S modifier to include system objects. If +
is appended to the command name, each object is listed with its associated
description.
\dC[+] [ pattern ]
Lists type casts. If pattern is specified, only casts whose source or target types
match the pattern are listed. If + is appended to the command name, each object is
listed with its associated description.
\dd[S] [ pattern ]
Shows the descriptions of objects of type constraint, operator class, operator family,
rule, and trigger. All other comments may be viewed by the respective backslash
commands for those object types.
\dd displays descriptions for objects matching the pattern, or of visible objects of
the appropriate type if no argument is given. But in either case, only objects that
have a description are listed. By default, only user-created objects are shown; supply
a pattern or the S modifier to include system objects.
Descriptions for objects can be created with the COMMENT(7) SQL command.
\dD[S+] [ pattern ]
Lists domains. If pattern is specified, only domains whose names match the pattern are
shown. By default, only user-created objects are shown; supply a pattern or the S
modifier to include system objects. If + is appended to the command name, each object
is listed with its associated permissions and description.
\ddp [ pattern ]
Lists default access privilege settings. An entry is shown for each role (and schema,
if applicable) for which the default privilege settings have been changed from the
built-in defaults. If pattern is specified, only entries whose role name or schema
name matches the pattern are listed.
The ALTER DEFAULT PRIVILEGES (ALTER_DEFAULT_PRIVILEGES(7)) command is used to set
default access privileges. The meaning of the privilege display is explained in
Section 5.7.
\dE[S+] [ pattern ]
\di[S+] [ pattern ]
\dm[S+] [ pattern ]
\ds[S+] [ pattern ]
\dt[S+] [ pattern ]
\dv[S+] [ pattern ]
In this group of commands, the letters E, i, m, s, t, and v stand for foreign table,
index, materialized view, sequence, table, and view, respectively. You can specify any
or all of these letters, in any order, to obtain a listing of objects of these types.
For example, \dit lists indexes and tables. If + is appended to the command name, each
object is listed with its physical size on disk and its associated description, if
any. If pattern is specified, only objects whose names match the pattern are listed.
By default, only user-created objects are shown; supply a pattern or the S modifier to
include system objects.
\des[+] [ pattern ]
Lists foreign servers (mnemonic: “external servers”). If pattern is specified, only
those servers whose name matches the pattern are listed. If the form \des+ is used, a
full description of each server is shown, including the server's access privileges,
type, version, options, and description.
\det[+] [ pattern ]
Lists foreign tables (mnemonic: “external tables”). If pattern is specified, only
entries whose table name or schema name matches the pattern are listed. If the form
\det+ is used, generic options and the foreign table description are also displayed.
\deu[+] [ pattern ]
Lists user mappings (mnemonic: “external users”). If pattern is specified, only those
mappings whose user names match the pattern are listed. If the form \deu+ is used,
additional information about each mapping is shown.
Caution
\deu+ might also display the user name and password of the remote user, so care
should be taken not to disclose them.
\dew[+] [ pattern ]
Lists foreign-data wrappers (mnemonic: “external wrappers”). If pattern is specified,
only those foreign-data wrappers whose name matches the pattern are listed. If the
form \dew+ is used, the access privileges, options, and description of the
foreign-data wrapper are also shown.
\df[anptwS+] [ pattern ]
Lists functions, together with their result data types, argument data types, and
function types, which are classified as “agg” (aggregate), “normal”, “procedure”,
“trigger”, or “window”. To display only functions of specific type(s), add the
corresponding letters a, n, p, t, or w to the command. If pattern is specified, only
functions whose names match the pattern are shown. By default, only user-created
objects are shown; supply a pattern or the S modifier to include system objects. If
the form \df+ is used, additional information about each function is shown, including
volatility, parallel safety, owner, security classification, access privileges,
language, source code and description.
Tip
To look up functions taking arguments or returning values of a specific data type,
use your pager's search capability to scroll through the \df output.
\dF[+] [ pattern ]
Lists text search configurations. If pattern is specified, only configurations whose
names match the pattern are shown. If the form \dF+ is used, a full description of
each configuration is shown, including the underlying text search parser and the
dictionary list for each parser token type.
\dFd[+] [ pattern ]
Lists text search dictionaries. If pattern is specified, only dictionaries whose names
match the pattern are shown. If the form \dFd+ is used, additional information is
shown about each selected dictionary, including the underlying text search template
and the option values.
\dFp[+] [ pattern ]
Lists text search parsers. If pattern is specified, only parsers whose names match the
pattern are shown. If the form \dFp+ is used, a full description of each parser is
shown, including the underlying functions and the list of recognized token types.
\dFt[+] [ pattern ]
Lists text search templates. If pattern is specified, only templates whose names match
the pattern are shown. If the form \dFt+ is used, additional information is shown
about each template, including the underlying function names.
\dg[S+] [ pattern ]
Lists database roles. (Since the concepts of “users” and “groups” have been unified
into “roles”, this command is now equivalent to \du.) By default, only user-created
roles are shown; supply the S modifier to include system roles. If pattern is
specified, only those roles whose names match the pattern are listed. If the form \dg+
is used, additional information is shown about each role; currently this adds the
comment for each role.
\dl
This is an alias for \lo_list, which shows a list of large objects.
\dL[S+] [ pattern ]
Lists procedural languages. If pattern is specified, only languages whose names match
the pattern are listed. By default, only user-created languages are shown; supply the
S modifier to include system objects. If + is appended to the command name, each
language is listed with its call handler, validator, access privileges, and whether it
is a system object.
\dn[S+] [ pattern ]
Lists schemas (namespaces). If pattern is specified, only schemas whose names match
the pattern are listed. By default, only user-created objects are shown; supply a
pattern or the S modifier to include system objects. If + is appended to the command
name, each object is listed with its associated permissions and description, if any.
\do[S+] [ pattern ]
Lists operators with their operand and result types. If pattern is specified, only
operators whose names match the pattern are listed. By default, only user-created
objects are shown; supply a pattern or the S modifier to include system objects. If +
is appended to the command name, additional information about each operator is shown,
currently just the name of the underlying function.
\dO[S+] [ pattern ]
Lists collations. If pattern is specified, only collations whose names match the
pattern are listed. By default, only user-created objects are shown; supply a pattern
or the S modifier to include system objects. If + is appended to the command name,
each collation is listed with its associated description, if any. Note that only
collations usable with the current database's encoding are shown, so the results may
vary in different databases of the same installation.
\dp [ pattern ]
Lists tables, views and sequences with their associated access privileges. If pattern
is specified, only tables, views and sequences whose names match the pattern are
listed.
The GRANT(7) and REVOKE(7) commands are used to set access privileges. The meaning of
the privilege display is explained in Section 5.7.
\dP[itn+] [ pattern ]
Lists partitioned relations. If pattern is specified, only entries whose name matches
the pattern are listed. The modifiers t (tables) and i (indexes) can be appended to
the command, filtering the kind of relations to list. By default, partitioned tables
and indexes are listed.
If the modifier n (“nested”) is used, or a pattern is specified, then non-root
partitioned relations are included, and a column is shown displaying the parent of
each partitioned relation.
If + is appended to the command name, the sum of the sizes of each relation's
partitions is also displayed, along with the relation's description. If n is combined
with +, two sizes are shown: one including the total size of directly-attached leaf
partitions, and another showing the total size of all partitions, including indirectly
attached sub-partitions.
\drds [ role-pattern [ database-pattern ] ]
Lists defined configuration settings. These settings can be role-specific,
database-specific, or both. role-pattern and database-pattern are used to select
specific roles and databases to list, respectively. If omitted, or if * is specified,
all settings are listed, including those not role-specific or database-specific,
respectively.
The ALTER ROLE (ALTER_ROLE(7)) and ALTER DATABASE (ALTER_DATABASE(7)) commands are
used to define per-role and per-database configuration settings.
\dRp[+] [ pattern ]
Lists replication publications. If pattern is specified, only those publications whose
names match the pattern are listed. If + is appended to the command name, the tables
associated with each publication are shown as well.
\dRs[+] [ pattern ]
Lists replication subscriptions. If pattern is specified, only those subscriptions
whose names match the pattern are listed. If + is appended to the command name,
additional properties of the subscriptions are shown.
\dT[S+] [ pattern ]
Lists data types. If pattern is specified, only types whose names match the pattern
are listed. If + is appended to the command name, each type is listed with its
internal name and size, its allowed values if it is an enum type, and its associated
permissions. By default, only user-created objects are shown; supply a pattern or the
S modifier to include system objects.
\du[S+] [ pattern ]
Lists database roles. (Since the concepts of “users” and “groups” have been unified
into “roles”, this command is now equivalent to \dg.) By default, only user-created
roles are shown; supply the S modifier to include system roles. If pattern is
specified, only those roles whose names match the pattern are listed. If the form \du+
is used, additional information is shown about each role; currently this adds the
comment for each role.
\dx[+] [ pattern ]
Lists installed extensions. If pattern is specified, only those extensions whose names
match the pattern are listed. If the form \dx+ is used, all the objects belonging to
each matching extension are listed.
\dy[+] [ pattern ]
Lists event triggers. If pattern is specified, only those event triggers whose names
match the pattern are listed. If + is appended to the command name, each object is
listed with its associated description.
\e or \edit [ filename ] [ line_number ]
If filename is specified, the file is edited; after the editor exits, the file's
content is copied into the current query buffer. If no filename is given, the current
query buffer is copied to a temporary file which is then edited in the same fashion.
Or, if the current query buffer is empty, the most recently executed query is copied
to a temporary file and edited in the same fashion.
The new contents of the query buffer are then re-parsed according to the normal rules
of psql, treating the whole buffer as a single line. Any complete queries are
immediately executed; that is, if the query buffer contains or ends with a semicolon,
everything up to that point is executed. Whatever remains will wait in the query
buffer; type semicolon or \g to send it, or \r to cancel it by clearing the query
buffer. Treating the buffer as a single line primarily affects meta-commands: whatever
is in the buffer after a meta-command will be taken as argument(s) to the
meta-command, even if it spans multiple lines. (Thus you cannot make
meta-command-using scripts this way. Use \i for that.)
If a line number is specified, psql will position the cursor on the specified line of
the file or query buffer. Note that if a single all-digits argument is given, psql
assumes it is a line number, not a file name.
Tip
See under ENVIRONMENT for how to configure and customize your editor.
\echo text [ ... ]
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:
=> \echo `date`
Tue Oct 26 21:40:57 CEST 1999
If the first argument is an unquoted -n the trailing newline is not written.
Tip
If you use the \o command to redirect your query output you might wish to use
\qecho instead of this command.
\ef [ function_description [ line_number ] ]
This command fetches and edits the definition of the named function or procedure, in
the form of a CREATE OR REPLACE FUNCTION or CREATE OR REPLACE PROCEDURE command.
Editing is done in the same way as for \edit. After the editor exits, the updated
command waits in the query buffer; type semicolon or \g to send it, or \r to cancel.
The target function can be specified by name alone, or by name and arguments, for
example foo(integer, text). The argument types must be given if there is more than one
function of the same name.
If no function is specified, a blank CREATE FUNCTION template is presented for
editing.
If a line number is specified, psql will position the cursor on the specified line of
the function body. (Note that the function body typically does not begin on the first
line of the file.)
Unlike most other meta-commands, the entire remainder of the line is always taken to
be the argument(s) of \ef, and neither variable interpolation nor backquote expansion
are performed in the arguments.
Tip
See under ENVIRONMENT for how to configure and customize your editor.
\encoding [ encoding ]
Sets the client character set encoding. Without an argument, this command shows the
current encoding.
\errverbose
Repeats the most recent server error message at maximum verbosity, as though VERBOSITY
were set to verbose and SHOW_CONTEXT were set to always.
\ev [ view_name [ line_number ] ]
This command fetches and edits the definition of the named view, in the form of a
CREATE OR REPLACE VIEW command. Editing is done in the same way as for \edit. After
the editor exits, the updated command waits in the query buffer; type semicolon or \g
to send it, or \r to cancel.
If no view is specified, a blank CREATE VIEW template is presented for editing.
If a line number is specified, psql will position the cursor on the specified line of
the view definition.
Unlike most other meta-commands, the entire remainder of the line is always taken to
be the argument(s) of \ev, and neither variable interpolation nor backquote expansion
are performed in the arguments.
\f [ string ]
Sets the field separator for unaligned query output. The default is the vertical bar
(|). It is equivalent to \pset fieldsep.
\g [ filename ]
\g [ |command ]
Sends the current query buffer to the server for execution. If an argument is given,
the query's output is written to the named file or piped to the given shell command,
instead of displaying it as usual. The file or command is written to only if the query
successfully returns zero or more tuples, not if the query fails or is a
non-data-returning SQL command.
If the current query buffer is empty, the most recently sent query is re-executed
instead. Except for that behavior, \g without an argument is essentially equivalent to
a semicolon. A \g with argument is a “one-shot” alternative to the \o command.
If the argument begins with |, then the entire remainder of the line is taken to be
the command to execute, and neither variable interpolation nor backquote expansion are
performed in it. The rest of the line is simply passed literally to the shell.
\gdesc
Shows the description (that is, the column names and data types) of the result of the
current query buffer. The query is not actually executed; however, if it contains some
type of syntax error, that error will be reported in the normal way.
If the current query buffer is empty, the most recently sent query is described
instead.
\gexec
Sends the current query buffer to the server, then treats each column of each row of
the query's output (if any) as a SQL statement to be executed. For example, to create
an index on each column of my_table:
=> SELECT format('create index on my_table(%I)', attname)
-> FROM pg_attribute
-> WHERE attrelid = 'my_table'::regclass AND attnum > 0
-> ORDER BY attnum
-> \gexec
CREATE INDEX
CREATE INDEX
CREATE INDEX
CREATE INDEX
The generated queries are executed in the order in which the rows are returned, and
left-to-right within each row if there is more than one column. NULL fields are
ignored. The generated queries are sent literally to the server for processing, so
they cannot be psql meta-commands nor contain psql variable references. If any
individual query fails, execution of the remaining queries continues unless
ON_ERROR_STOP is set. Execution of each query is subject to ECHO processing. (Setting
ECHO to all or queries is often advisable when using \gexec.) Query logging,
single-step mode, timing, and other query execution features apply to each generated
query as well.
If the current query buffer is empty, the most recently sent query is re-executed
instead.
\gset [ prefix ]
Sends the current query buffer to the server and stores the query's output into psql
variables (see Variables). The query to be executed must return exactly one row. Each
column of the row is stored into a separate variable, named the same as the column.
For example:
=> SELECT 'hello' AS var1, 10 AS var2
-> \gset
=> \echo :var1 :var2
hello 10
If you specify a prefix, that string is prepended to the query's column names to
create the variable names to use:
=> SELECT 'hello' AS var1, 10 AS var2
-> \gset result_
=> \echo :result_var1 :result_var2
hello 10
If a column result is NULL, the corresponding variable is unset rather than being set.
If the query fails or does not return one row, no variables are changed.
If the current query buffer is empty, the most recently sent query is re-executed
instead.
\gx [ filename ]
\gx [ |command ]
\gx is equivalent to \g, but forces expanded output mode for this query. See \x.
\h or \help [ command ]
Gives syntax help on the specified SQL command. If command is not specified, then psql
will list all the commands for which syntax help is available. If command is an
asterisk (*), then syntax help on all SQL commands is shown.
Unlike most other meta-commands, the entire remainder of the line is always taken to
be the argument(s) of \help, and neither variable interpolation nor backquote
expansion are performed in the arguments.
Note
To simplify typing, commands that consists of several words do not have to be
quoted. Thus it is fine to type \help alter table.
\H or \html
Turns on HTML query output format. If the HTML format is already on, it is switched
back to the default aligned text format. This command is for compatibility and
convenience, but see \pset about setting other output options.
\i or \include filename
Reads input from the file filename and executes it as though it had been typed on the
keyboard.
If filename is - (hyphen), then standard input is read until an EOF indication or \q
meta-command. This can be used to intersperse interactive input with input from files.
Note that Readline behavior will be used only if it is active at the outermost level.
Note
If you want to see the lines on the screen as they are read you must set the
variable ECHO to all.
\if expression
\elif expression
\else
\endif
This group of commands implements nestable conditional blocks. A conditional block
must begin with an \if and end with an \endif. In between there may be any number of
\elif clauses, which may optionally be followed by a single \else clause. Ordinary
queries and other types of backslash commands may (and usually do) appear between the
commands forming a conditional block.
The \if and \elif commands read their argument(s) and evaluate them as a boolean
expression. If the expression yields true then processing continues normally;
otherwise, lines are skipped until a matching \elif, \else, or \endif is reached. Once
an \if or \elif test has succeeded, the arguments of later \elif commands in the same
block are not evaluated but are treated as false. Lines following an \else are
processed only if no earlier matching \if or \elif succeeded.
The expression argument of an \if or \elif command is subject to variable
interpolation and backquote expansion, just like any other backslash command argument.
After that it is evaluated like the value of an on/off option variable. So a valid
value is any unambiguous case-insensitive match for one of: true, false, 1, 0, on,
off, yes, no. For example, t, T, and tR will all be considered to be true.
Expressions that do not properly evaluate to true or false will generate a warning and
be treated as false.
Lines being skipped are parsed normally to identify queries and backslash commands,
but queries are not sent to the server, and backslash commands other than conditionals
(\if, \elif, \else, \endif) are ignored. Conditional commands are checked only for
valid nesting. Variable references in skipped lines are not expanded, and backquote
expansion is not performed either.
All the backslash commands of a given conditional block must appear in the same source
file. If EOF is reached on the main input file or an \include-ed file before all local
\if-blocks have been closed, then psql will raise an error.
Here is an example:
-- check for the existence of two separate records in the database and store
-- the results in separate psql variables
SELECT
EXISTS(SELECT 1 FROM customer WHERE customer_id = 123) as is_customer,
EXISTS(SELECT 1 FROM employee WHERE employee_id = 456) as is_employee
\gset
\if :is_customer
SELECT * FROM customer WHERE customer_id = 123;
\elif :is_employee
\echo 'is not a customer but is an employee'
SELECT * FROM employee WHERE employee_id = 456;
\else
\if yes
\echo 'not a customer or employee'
\else
\echo 'this will never print'
\endif
\endif
\ir or \include_relative filename
The \ir command is similar to \i, but resolves relative file names differently. When
executing in interactive mode, the two commands behave identically. However, when
invoked from a script, \ir interprets file names relative to the directory in which
the script is located, rather than the current working directory.
\l[+] or \list[+] [ pattern ]
List the databases in the server and show their names, owners, character set
encodings, and access privileges. If pattern is specified, only databases whose names
match the pattern are listed. If + is appended to the command name, database sizes,
default tablespaces, and descriptions are also displayed. (Size information is only
available for databases that the current user can connect to.)
\lo_export loid filename
Reads the large object with OID loid from the database and writes it to filename. Note
that this is subtly different from the server function lo_export, which acts with the
permissions of the user that the database server runs as and on the server's file
system.
Tip
Use \lo_list to find out the large object's OID.
\lo_import filename [ comment ]
Stores the file into a PostgreSQL large object. Optionally, it associates the given
comment with the object. Example:
foo=> \lo_import '/home/peter/pictures/photo.xcf' 'a picture of me'
lo_import 152801
The response indicates that the large object received object ID 152801, which can be
used to access the newly-created large object in the future. For the sake of
readability, it is recommended to always associate a human-readable comment with every
object. Both OIDs and comments can be viewed with the \lo_list command.
Note that this command is subtly different from the server-side lo_import because it
acts as the local user on the local file system, rather than the server's user and
file system.
\lo_list
Shows a list of all PostgreSQL large objects currently stored in the database, along
with any comments provided for them.
\lo_unlink loid
Deletes the large object with OID loid from the database.
Tip
Use \lo_list to find out the large object's OID.
\o or \out [ filename ]
\o or \out [ |command ]
Arranges to save future query results to the file filename or pipe future results to
the shell command command. If no argument is specified, the query output is reset to
the standard output.
If the argument begins with |, then the entire remainder of the line is taken to be
the command to execute, and neither variable interpolation nor backquote expansion are
performed in it. The rest of the line is simply passed literally to the shell.
“Query results” includes all tables, command responses, and notices obtained from the
database server, as well as output of various backslash commands that query the
database (such as \d); but not error messages.
Tip
To intersperse text output in between query results, use \qecho.
\p or \print
Print the current query buffer to the standard output. If the current query buffer is
empty, the most recently executed query is printed instead.
\password [ username ]
Changes the password of the specified user (by default, the current user). This
command prompts for the new password, encrypts it, and sends it to the server as an
ALTER ROLE command. This makes sure that the new password does not appear in cleartext
in the command history, the server log, or elsewhere.
\prompt [ text ] name
Prompts the user to supply text, which is assigned to the variable name. An optional
prompt string, text, can be specified. (For multiword prompts, surround the text with
single quotes.)
By default, \prompt uses the terminal for input and output. However, if the -f command
line switch was used, \prompt uses standard input and standard output.
\pset [ option [ value ] ]
This command sets options affecting the output of query result tables. option
indicates which option is to be set. The semantics of value vary depending on the
selected option. For some options, omitting value causes the option to be toggled or
unset, as described under the particular option. If no such behavior is mentioned,
then omitting value just results in the current setting being displayed.
\pset without any arguments displays the current status of all printing options.
Adjustable printing options are:
border
The value must be a number. In general, the higher the number the more borders and
lines the tables will have, but details depend on the particular format. In HTML
format, this will translate directly into the border=... attribute. In most other
formats only values 0 (no border), 1 (internal dividing lines), and 2 (table
frame) make sense, and values above 2 will be treated the same as border = 2. The
latex and latex-longtable formats additionally allow a value of 3 to add dividing
lines between data rows.
columns
Sets the target width for the wrapped format, and also the width limit for
determining whether output is wide enough to require the pager or switch to the
vertical display in expanded auto mode. Zero (the default) causes the target width
to be controlled by the environment variable COLUMNS, or the detected screen width
if COLUMNS is not set. In addition, if columns is zero then the wrapped format
only affects screen output. If columns is nonzero then file and pipe output is
wrapped to that width as well.
csv_fieldsep
Specifies the field separator to be used in CSV output format. If the separator
character appears in a field's value, that field is output within double quotes,
following standard CSV rules. The default is a comma.
expanded (or x)
If value is specified it must be either on or off, which will enable or disable
expanded mode, or auto. If value is omitted the command toggles between the on and
off settings. When expanded mode is enabled, query results are displayed in two
columns, with the column name on the left and the data on the right. This mode is
useful if the data wouldn't fit on the screen in the normal “horizontal” mode. In
the auto setting, the expanded mode is used whenever the query output has more
than one column and is wider than the screen; otherwise, the regular mode is used.
The auto setting is only effective in the aligned and wrapped formats. In other
formats, it always behaves as if the expanded mode is off.
fieldsep
Specifies the field separator to be used in unaligned output format. That way one
can create, for example, tab-separated output, which other programs might prefer.
To set a tab as field separator, type \pset fieldsep '\t'. The default field
separator is '|' (a vertical bar).
fieldsep_zero
Sets the field separator to use in unaligned output format to a zero byte.
footer
If value is specified it must be either on or off which will enable or disable
display of the table footer (the (n rows) count). If value is omitted the command
toggles footer display on or off.
format
Sets the output format to one of aligned, asciidoc, csv, html, latex,
latex-longtable, troff-ms, unaligned, or wrapped. Unique abbreviations are
allowed.
aligned format is the standard, human-readable, nicely formatted text output; this
is the default.
unaligned format writes all columns of a row on one line, separated by the
currently active field separator. This is useful for creating output that might be
intended to be read in by other programs, for example, tab-separated or
comma-separated format. However, the field separator character is not treated
specially if it appears in a column's value; so CSV format may be better suited
for such purposes.
csv format
writes column values separated by commas, applying the quoting rules described in
RFC 4180. This output is compatible with the CSV format of the server's COPY
command. A header line with column names is generated unless the tuples_only
parameter is on. Titles and footers are not printed. Each row is terminated by the
system-dependent end-of-line character, which is typically a single newline (\n)
for Unix-like systems or a carriage return and newline sequence (\r\n) for
Microsoft Windows. Field separator characters other than comma can be selected
with \pset csv_fieldsep.
wrapped format is like aligned but wraps wide data values across lines to make the
output fit in the target column width. The target width is determined as described
under the columns option. Note that psql will not attempt to wrap column header
titles; therefore, wrapped format behaves the same as aligned if the total width
needed for column headers exceeds the target.
The asciidoc, html, latex, latex-longtable, and troff-ms formats put out tables
that are intended to be included in documents using the respective mark-up
language. They are not complete documents! This might not be necessary in HTML,
but in LaTeX you must have a complete document wrapper. The latex format uses
LaTeX's tabular environment. The latex-longtable format requires the LaTeX
longtable and booktabs packages.
linestyle
Sets the border line drawing style to one of ascii, old-ascii, or unicode. Unique
abbreviations are allowed. (That would mean one letter is enough.) The default
setting is ascii. This option only affects the aligned and wrapped output formats.
ascii style uses plain ASCII characters. Newlines in data are shown using a +
symbol in the right-hand margin. When the wrapped format wraps data from one line
to the next without a newline character, a dot (.) is shown in the right-hand
margin of the first line, and again in the left-hand margin of the following line.
old-ascii style uses plain ASCII characters, using the formatting style used in
PostgreSQL 8.4 and earlier. Newlines in data are shown using a : symbol in place
of the left-hand column separator. When the data is wrapped from one line to the
next without a newline character, a ; symbol is used in place of the left-hand
column separator.
unicode style uses Unicode box-drawing characters. Newlines in data are shown
using a carriage return symbol in the right-hand margin. When the data is wrapped
from one line to the next without a newline character, an ellipsis symbol is shown
in the right-hand margin of the first line, and again in the left-hand margin of
the following line.
When the border setting is greater than zero, the linestyle option also determines
the characters with which the border lines are drawn. Plain ASCII characters work
everywhere, but Unicode characters look nicer on displays that recognize them.
null
Sets the string to be printed in place of a null value. The default is to print
nothing, which can easily be mistaken for an empty string. For example, one might
prefer \pset null '(null)'.
numericlocale
If value is specified it must be either on or off which will enable or disable
display of a locale-specific character to separate groups of digits to the left of
the decimal marker. If value is omitted the command toggles between regular and
locale-specific numeric output.
pager
Controls use of a pager program for query and psql help output. If the environment
variable PSQL_PAGER or PAGER is set, the output is piped to the specified program.
Otherwise a platform-dependent default program (such as more) is used.
When the pager option is off, the pager program is not used. When the pager option
is on, the pager is used when appropriate, i.e., when the output is to a terminal
and will not fit on the screen. The pager option can also be set to always, which
causes the pager to be used for all terminal output regardless of whether it fits
on the screen. \pset pager without a value toggles pager use on and off.
pager_min_lines
If pager_min_lines is set to a number greater than the page height, the pager
program will not be called unless there are at least this many lines of output to
show. The default setting is 0.
recordsep
Specifies the record (line) separator to use in unaligned output format. The
default is a newline character.
recordsep_zero
Sets the record separator to use in unaligned output format to a zero byte.
tableattr (or T)
In HTML format, this specifies attributes to be placed inside the table tag. This
could for example be cellpadding or bgcolor. Note that you probably don't want to
specify border here, as that is already taken care of by \pset border. If no value
is given, the table attributes are unset.
In latex-longtable format, this controls the proportional width of each column
containing a left-aligned data type. It is specified as a whitespace-separated
list of values, e.g., '0.2 0.2 0.6'. Unspecified output columns use the last
specified value.
title (or C)
Sets the table title for any subsequently printed tables. This can be used to give
your output descriptive tags. If no value is given, the title is unset.
tuples_only (or t)
If value is specified it must be either on or off which will enable or disable
tuples-only mode. If value is omitted the command toggles between regular and
tuples-only output. Regular output includes extra information such as column
headers, titles, and various footers. In tuples-only mode, only actual table data
is shown.
unicode_border_linestyle
Sets the border drawing style for the unicode line style to one of single or
double.
unicode_column_linestyle
Sets the column drawing style for the unicode line style to one of single or
double.
unicode_header_linestyle
Sets the header drawing style for the unicode line style to one of single or
double.
Illustrations of how these different formats look can be seen in the EXAMPLES section.
Tip
There are various shortcut commands for \pset. See \a, \C, \f, \H, \t, \T, and \x.
\q or \quit
Quits the psql program. In a script file, only execution of that script is terminated.
\qecho text [ ... ]
This command is identical to \echo except that the output will be written to the query
output channel, as set by \o.
\r or \reset
Resets (clears) the query buffer.
\s [ filename ]
Print psql's command line history to filename. If filename is omitted, the history is
written to the standard output (using the pager if appropriate). This command is not
available if psql was built without Readline support.
\set [ name [ value [ ... ] ] ]
Sets the psql variable name to value, or if more than one value is given, to the
concatenation of all of them. If only one argument is given, the variable is set to an
empty-string value. To unset a variable, use the \unset command.
\set without any arguments displays the names and values of all currently-set psql
variables.
Valid variable names can contain letters, digits, and underscores. See the section
Variables below for details. Variable names are case-sensitive.
Certain variables are special, in that they control psql's behavior or are
automatically set to reflect connection state. These variables are documented in
Variables, below.
Note
This command is unrelated to the SQL command SET(7).
\setenv name [ value ]
Sets the environment variable name to value, or if the value is not supplied, unsets
the environment variable. Example:
testdb=> \setenv PAGER less
testdb=> \setenv LESS -imx4F
\sf[+] function_description
This command fetches and shows the definition of the named function or procedure, in
the form of a CREATE OR REPLACE FUNCTION or CREATE OR REPLACE PROCEDURE command. The
definition is printed to the current query output channel, as set by \o.
The target function can be specified by name alone, or by name and arguments, for
example foo(integer, text). The argument types must be given if there is more than one
function of the same name.
If + is appended to the command name, then the output lines are numbered, with the
first line of the function body being line 1.
Unlike most other meta-commands, the entire remainder of the line is always taken to
be the argument(s) of \sf, and neither variable interpolation nor backquote expansion
are performed in the arguments.
\sv[+] view_name
This command fetches and shows the definition of the named view, in the form of a
CREATE OR REPLACE VIEW command. The definition is printed to the current query output
channel, as set by \o.
If + is appended to the command name, then the output lines are numbered from 1.
Unlike most other meta-commands, the entire remainder of the line is always taken to
be the argument(s) of \sv, and neither variable interpolation nor backquote expansion
are performed in the arguments.
\t
Toggles the display of output column name headings and row count footer. This command
is equivalent to \pset tuples_only and is provided for convenience.
\T table_options
Specifies attributes to be placed within the table tag in HTML output format. This
command is equivalent to \pset tableattr table_options.
\timing [ on | off ]
With a parameter, turns displaying of how long each SQL statement takes on or off.
Without a parameter, toggles the display between on and off. The display is in
milliseconds; intervals longer than 1 second are also shown in minutes:seconds format,
with hours and days fields added if needed.
\unset name
Unsets (deletes) the psql variable name.
Most variables that control psql's behavior cannot be unset; instead, an \unset
command is interpreted as setting them to their default values. See Variables, below.
\w or \write filename
\w or \write |command
Writes the current query buffer to the file filename or pipes it to the shell command
command. If the current query buffer is empty, the most recently executed query is
written instead.
If the argument begins with |, then the entire remainder of the line is taken to be
the command to execute, and neither variable interpolation nor backquote expansion are
performed in it. The rest of the line is simply passed literally to the shell.
\watch [ seconds ]
Repeatedly execute the current query buffer (as \g does) until interrupted or the
query fails. Wait the specified number of seconds (default 2) between executions. Each
query result is displayed with a header that includes the \pset title string (if any),
the time as of query start, and the delay interval.
If the current query buffer is empty, the most recently sent query is re-executed
instead.
\x [ on | off | auto ]
Sets or toggles expanded table formatting mode. As such it is equivalent to \pset
expanded.
\z [ pattern ]
Lists tables, views and sequences with their associated access privileges. If a
pattern is specified, only tables, views and sequences whose names match the pattern
are listed.
This is an alias for \dp (“display privileges”).
\! [ command ]
With no argument, escapes to a sub-shell; psql resumes when the sub-shell exits. With
an argument, executes the shell command command.
Unlike most other meta-commands, the entire remainder of the line is always taken to
be the argument(s) of \!, and neither variable interpolation nor backquote expansion
are performed in the arguments. The rest of the line is simply passed literally to the
shell.
\? [ topic ]
Shows help information. The optional topic parameter (defaulting to commands) selects
which part of psql is explained: commands describes psql's backslash commands; options
describes the command-line options that can be passed to psql; and variables shows
help about psql configuration variables.
\;
Backslash-semicolon is not a meta-command in the same way as the preceding commands;
rather, it simply causes a semicolon to be added to the query buffer without any
further processing.
Normally, psql will dispatch a SQL command to the server as soon as it reaches the
command-ending semicolon, even if more input remains on the current line. Thus for
example entering
select 1; select 2; select 3;
will result in the three SQL commands being individually sent to the server, with each
one's results being displayed before continuing to the next command. However, a
semicolon entered as \; will not trigger command processing, so that the command
before it and the one after are effectively combined and sent to the server in one
request. So for example
select 1\; select 2\; select 3;
results in sending the three SQL commands to the server in a single request, when the
non-backslashed semicolon is reached. The server executes such a request as a single
transaction, unless there are explicit BEGIN/COMMIT commands included in the string to
divide it into multiple transactions. (See Section 52.2.2.1 for more details about how
the server handles multi-query strings.) psql prints only the last query result it
receives for each request; in this example, although all three SELECTs are indeed
executed, psql only prints the 3.
Patterns
The various \d commands accept a pattern parameter to specify the object name(s) to be
displayed. In the simplest case, a pattern is just the exact name of the object. The
characters within a pattern are normally folded to lower case, just as in SQL names;
for example, \dt FOO will display the table named foo. As in SQL names, placing double
quotes around a pattern stops folding to lower case. Should you need to include an
actual double quote character in a pattern, write it as a pair of double quotes within
a double-quote sequence; again this is in accord with the rules for SQL quoted
identifiers. For example, \dt "FOO""BAR" will display the table named FOO"BAR (not
foo"bar). Unlike the normal rules for SQL names, you can put double quotes around just
part of a pattern, for instance \dt FOO"FOO"BAR will display the table named
fooFOObar.
Whenever the pattern parameter is omitted completely, the \d commands display all
objects that are visible in the current schema search path — this is equivalent to
using * as the pattern. (An object is said to be visible if its containing schema is
in the search path and no object of the same kind and name appears earlier in the
search path. This is equivalent to the statement that the object can be referenced by
name without explicit schema qualification.) To see all objects in the database
regardless of visibility, use *.* as the pattern.
Within a pattern, * matches any sequence of characters (including no characters) and ?
matches any single character. (This notation is comparable to Unix shell file name
patterns.) For example, \dt int* displays tables whose names begin with int. But
within double quotes, * and ? lose these special meanings and are just matched
literally.
A pattern that contains a dot (.) is interpreted as a schema name pattern followed by
an object name pattern. For example, \dt foo*.*bar* displays all tables whose table
name includes bar that are in schemas whose schema name starts with foo. When no dot
appears, then the pattern matches only objects that are visible in the current schema
search path. Again, a dot within double quotes loses its special meaning and is
matched literally.
Advanced users can use regular-expression notations such as character classes, for
example [0-9] to match any digit. All regular expression special characters work as
specified in Section 9.7.3, except for . which is taken as a separator as mentioned
above, * which is translated to the regular-expression notation .*, ? which is
translated to ., and $ which is matched literally. You can emulate these pattern
characters at need by writing ? for ., (R+|) for R*, or (R|) for R?. $ is not needed
as a regular-expression character since the pattern must match the whole name, unlike
the usual interpretation of regular expressions (in other words, $ is automatically
appended to your pattern). Write * at the beginning and/or end if you don't wish the
pattern to be anchored. Note that within double quotes, all regular expression special
characters lose their special meanings and are matched literally. Also, the regular
expression special characters are matched literally in operator name patterns (i.e.,
the argument of \do).
Advanced Features
Variables
psql provides variable substitution features similar to common Unix command shells.
Variables are simply name/value pairs, where the value can be any string of any
length. The name must consist of letters (including non-Latin letters), digits, and
underscores.
To set a variable, use the psql meta-command \set. For example,
testdb=> \set foo bar
sets the variable foo to the value bar. To retrieve the content of the variable,
precede the name with a colon, for example:
testdb=> \echo :foo
bar
This works in both regular SQL commands and meta-commands; there is more detail in SQL
Interpolation, below.
If you call \set without a second argument, the variable is set to an empty-string
value. To unset (i.e., delete) a variable, use the command \unset. To show the values
of all variables, call \set without any argument.
Note
The arguments of \set are subject to the same substitution rules as with other
commands. Thus you can construct interesting references such as \set :foo
'something' and get “soft links” or “variable variables” of Perl or PHP fame,
respectively. Unfortunately (or fortunately?), there is no way to do anything
useful with these constructs. On the other hand, \set bar :foo is a perfectly
valid way to copy a variable.
A number of these variables are treated specially by psql. They represent certain
option settings that can be changed at run time by altering the value of the variable,
or in some cases represent changeable state of psql. By convention, all specially
treated variables' names consist of all upper-case ASCII letters (and possibly digits
and underscores). To ensure maximum compatibility in the future, avoid using such
variable names for your own purposes.
Variables that control psql's behavior generally cannot be unset or set to invalid
values. An \unset command is allowed but is interpreted as setting the variable to its
default value. A \set command without a second argument is interpreted as setting the
variable to on, for control variables that accept that value, and is rejected for
others. Also, control variables that accept the values on and off will also accept
other common spellings of Boolean values, such as true and false.
The specially treated variables are:
AUTOCOMMIT
When on (the default), each SQL command is automatically committed upon successful
completion. To postpone commit in this mode, you must enter a BEGIN or START
TRANSACTION SQL command. When off or unset, SQL commands are not committed until
you explicitly issue COMMIT or END. The autocommit-off mode works by issuing an
implicit BEGIN for you, just before any command that is not already in a
transaction block and is not itself a BEGIN or other transaction-control command,
nor a command that cannot be executed inside a transaction block (such as VACUUM).
Note
In autocommit-off mode, you must explicitly abandon any failed transaction by
entering ABORT or ROLLBACK. Also keep in mind that if you exit the session
without committing, your work will be lost.
Note
The autocommit-on mode is PostgreSQL's traditional behavior, but
autocommit-off is closer to the SQL spec. If you prefer autocommit-off, you
might wish to set it in the system-wide psqlrc file or your ~/.psqlrc file.
COMP_KEYWORD_CASE
Determines which letter case to use when completing an SQL key word. If set to
lower or upper, the completed word will be in lower or upper case, respectively.
If set to preserve-lower or preserve-upper (the default), the completed word will
be in the case of the word already entered, but words being completed without
anything entered will be in lower or upper case, respectively.
DBNAME
The name of the database you are currently connected to. This is set every time
you connect to a database (including program start-up), but can be changed or
unset.
ECHO
If set to all, all nonempty input lines are printed to standard output as they are
read. (This does not apply to lines read interactively.) To select this behavior
on program start-up, use the switch -a. If set to queries, psql prints each query
to standard output as it is sent to the server. The switch to select this behavior
is -e. If set to errors, then only failed queries are displayed on standard error
output. The switch for this behavior is -b. If set to none (the default), then no
queries are displayed.
ECHO_HIDDEN
When this variable is set to on and a backslash command queries the database, the
query is first shown. This feature helps you to study PostgreSQL internals and
provide similar functionality in your own programs. (To select this behavior on
program start-up, use the switch -E.) If you set this variable to the value
noexec, the queries are just shown but are not actually sent to the server and
executed. The default value is off.
ENCODING
The current client character set encoding. This is set every time you connect to a
database (including program start-up), and when you change the encoding with
\encoding, but it can be changed or unset.
ERROR
true if the last SQL query failed, false if it succeeded. See also SQLSTATE.
FETCH_COUNT
If this variable is set to an integer value greater than zero, the results of
SELECT queries are fetched and displayed in groups of that many rows, rather than
the default behavior of collecting the entire result set before display. Therefore
only a limited amount of memory is used, regardless of the size of the result set.
Settings of 100 to 1000 are commonly used when enabling this feature. Keep in mind
that when using this feature, a query might fail after having already displayed
some rows.
Tip
Although you can use any output format with this feature, the default aligned
format tends to look bad because each group of FETCH_COUNT rows will be
formatted separately, leading to varying column widths across the row groups.
The other output formats work better.
HIDE_TABLEAM
If this variable is set to true, a table's access method details are not
displayed. This is mainly useful for regression tests.
HISTCONTROL
If this variable is set to ignorespace, lines which begin with a space are not
entered into the history list. If set to a value of ignoredups, lines matching the
previous history line are not entered. A value of ignoreboth combines the two
options. If set to none (the default), all lines read in interactive mode are
saved on the history list.
Note
This feature was shamelessly plagiarized from Bash.
HISTFILE
The file name that will be used to store the history list. If unset, the file name
is taken from the PSQL_HISTORY environment variable. If that is not set either,
the default is ~/.psql_history, or %APPDATA%\postgresql\psql_history on Windows.
For example, putting:
\set HISTFILE ~/.psql_history- :DBNAME
in ~/.psqlrc will cause psql to maintain a separate history for each database.
Note
This feature was shamelessly plagiarized from Bash.
HISTSIZE
The maximum number of commands to store in the command history (default 500). If
set to a negative value, no limit is applied.
Note
This feature was shamelessly plagiarized from Bash.
HOST
The database server host you are currently connected to. This is set every time
you connect to a database (including program start-up), but can be changed or
unset.
IGNOREEOF
If set to 1 or less, sending an EOF character (usually Control+D) to an
interactive session of psql will terminate the application. If set to a larger
numeric value, that many consecutive EOF characters must be typed to make an
interactive session terminate. If the variable is set to a non-numeric value, it
is interpreted as 10. The default is 0.
Note
This feature was shamelessly plagiarized from Bash.
LASTOID
The value of the last affected OID, as returned from an INSERT or \lo_import
command. This variable is only guaranteed to be valid until after the result of
the next SQL command has been displayed. PostgreSQL servers since version 12 do
not support OID system columns anymore, thus LASTOID will always be 0 following
INSERT when targeting such servers.
LAST_ERROR_MESSAGE
LAST_ERROR_SQLSTATE
The primary error message and associated SQLSTATE code for the most recent failed
query in the current psql session, or an empty string and 00000 if no error has
occurred in the current session.
ON_ERROR_ROLLBACK
When set to on, if a statement in a transaction block generates an error, the
error is ignored and the transaction continues. When set to interactive, such
errors are only ignored in interactive sessions, and not when reading script
files. When set to off (the default), a statement in a transaction block that
generates an error aborts the entire transaction. The error rollback mode works by
issuing an implicit SAVEPOINT for you, just before each command that is in a
transaction block, and then rolling back to the savepoint if the command fails.
ON_ERROR_STOP
By default, command processing continues after an error. When this variable is set
to on, processing will instead stop immediately. In interactive mode, psql will
return to the command prompt; otherwise, psql will exit, returning error code 3 to
distinguish this case from fatal error conditions, which are reported using error
code 1. In either case, any currently running scripts (the top-level script, if
any, and any other scripts which it may have in invoked) will be terminated
immediately. If the top-level command string contained multiple SQL commands,
processing will stop with the current command.
PORT
The database server port to which you are currently connected. This is set every
time you connect to a database (including program start-up), but can be changed or
unset.
PROMPT1
PROMPT2
PROMPT3
These specify what the prompts psql issues should look like. See Prompting below.
QUIET
Setting this variable to on is equivalent to the command line option -q. It is
probably not too useful in interactive mode.
ROW_COUNT
The number of rows returned or affected by the last SQL query, or 0 if the query
failed or did not report a row count.
SERVER_VERSION_NAME
SERVER_VERSION_NUM
The server's version number as a string, for example 9.6.2, 10.1 or 11beta1, and
in numeric form, for example 90602 or 100001. These are set every time you connect
to a database (including program start-up), but can be changed or unset.
SHOW_CONTEXT
This variable can be set to the values never, errors, or always to control whether
CONTEXT fields are displayed in messages from the server. The default is errors
(meaning that context will be shown in error messages, but not in notice or
warning messages). This setting has no effect when VERBOSITY is set to terse or
sqlstate. (See also \errverbose, for use when you want a verbose version of the
error you just got.)
SINGLELINE
Setting this variable to on is equivalent to the command line option -S.
SINGLESTEP
Setting this variable to on is equivalent to the command line option -s.
SQLSTATE
The error code (see Appendix A) associated with the last SQL query's failure, or
00000 if it succeeded.
USER
The database user you are currently connected as. This is set every time you
connect to a database (including program start-up), but can be changed or unset.
VERBOSITY
This variable can be set to the values default, verbose, terse, or sqlstate to
control the verbosity of error reports. (See also \errverbose, for use when you
want a verbose version of the error you just got.)
VERSION
VERSION_NAME
VERSION_NUM
These variables are set at program start-up to reflect psql's version,
respectively as a verbose string, a short string (e.g., 9.6.2, 10.1, or 11beta1),
and a number (e.g., 90602 or 100001). They can be changed or unset.
SQL Interpolation
A key feature of psql variables is that you can substitute (“interpolate”) them into
regular SQL statements, as well as the arguments of meta-commands. Furthermore, psql
provides facilities for ensuring that variable values used as SQL literals and
identifiers are properly quoted. The syntax for interpolating a value without any
quoting is to prepend the variable name with a colon (:). For example,
testdb=> \set foo 'my_table'
testdb=> SELECT * FROM :foo;
would query the table my_table. Note that this may be unsafe: the value of the
variable is copied literally, so it can contain unbalanced quotes, or even backslash
commands. You must make sure that it makes sense where you put it.
When a value is to be used as an SQL literal or identifier, it is safest to arrange
for it to be quoted. To quote the value of a variable as an SQL literal, write a colon
followed by the variable name in single quotes. To quote the value as an SQL
identifier, write a colon followed by the variable name in double quotes. These
constructs deal correctly with quotes and other special characters embedded within the
variable value. The previous example would be more safely written this way:
testdb=> \set foo 'my_table'
testdb=> SELECT * FROM :"foo";
Variable interpolation will not be performed within quoted SQL literals and
identifiers. Therefore, a construction such as ':foo' doesn't work to produce a quoted
literal from a variable's value (and it would be unsafe if it did work, since it
wouldn't correctly handle quotes embedded in the value).
One example use of this mechanism is to copy the contents of a file into a table
column. First load the file into a variable and then interpolate the variable's value
as a quoted string:
testdb=> \set content `cat my_file.txt`
testdb=> INSERT INTO my_table VALUES (:'content');
(Note that this still won't work if my_file.txt contains NUL bytes. psql does not
support embedded NUL bytes in variable values.)
Since colons can legally appear in SQL commands, an apparent attempt at interpolation
(that is, :name, :'name', or :"name") is not replaced unless the named variable is
currently set. In any case, you can escape a colon with a backslash to protect it from
substitution.
The :{?name} special syntax returns TRUE or FALSE depending on whether the variable
exists or not, and is thus always substituted, unless the colon is backslash-escaped.
The colon syntax for variables is standard SQL for embedded query languages, such as
ECPG. The colon syntaxes for array slices and type casts are PostgreSQL extensions,
which can sometimes conflict with the standard usage. The colon-quote syntax for
escaping a variable's value as an SQL literal or identifier is a psql extension.
Prompting
The prompts psql issues can be customized to your preference. The three variables
PROMPT1, PROMPT2, and PROMPT3 contain strings and special escape sequences that
describe the appearance of the prompt. Prompt 1 is the normal prompt that is issued
when psql requests a new command. Prompt 2 is issued when more input is expected
during command entry, for example because the command was not terminated with a
semicolon or a quote was not closed. Prompt 3 is issued when you are running an SQL
COPY FROM STDIN command and you need to type in a row value on the terminal.
The value of the selected prompt variable is printed literally, except where a percent
sign (%) is encountered. Depending on the next character, certain other text is
substituted instead. Defined substitutions are:
%M
The full host name (with domain name) of the database server, or [local] if the
connection is over a Unix domain socket, or [local:/dir/name], if the Unix domain
socket is not at the compiled in default location.
%m
The host name of the database server, truncated at the first dot, or [local] if
the connection is over a Unix domain socket.
%>
The port number at which the database server is listening.
%n
The database session user name. (The expansion of this value might change during a
database session as the result of the command SET SESSION AUTHORIZATION.)
%/
The name of the current database.
%~
Like %/, but the output is ~ (tilde) if the database is your default database.
%#
If the session user is a database superuser, then a #, otherwise a >. (The
expansion of this value might change during a database session as the result of
the command SET SESSION AUTHORIZATION.)
%p
The process ID of the backend currently connected to.
%R
In prompt 1 normally =, but @ if the session is in an inactive branch of a
conditional block, or ^ if in single-line mode, or ! if the session is
disconnected from the database (which can happen if \connect fails). In prompt 2
%R is replaced by a character that depends on why psql expects more input: - if
the command simply wasn't terminated yet, but * if there is an unfinished /* ...
*/ comment, a single quote if there is an unfinished quoted string, a double quote
if there is an unfinished quoted identifier, a dollar sign if there is an
unfinished dollar-quoted string, or ( if there is an unmatched left parenthesis.
In prompt 3 %R doesn't produce anything.
%x
Transaction status: an empty string when not in a transaction block, or * when in
a transaction block, or ! when in a failed transaction block, or ? when the
transaction state is indeterminate (for example, because there is no connection).
%l
The line number inside the current statement, starting from 1.
%digits
The character with the indicated octal code is substituted.
%:name:
The value of the psql variable name. See the section Variables for details.
%`command`
The output of command, similar to ordinary “back-tick” substitution.
%[ ... %]
Prompts can contain terminal control characters which, for example, change the
color, background, or style of the prompt text, or change the title of the
terminal window. In order for the line editing features of Readline to work
properly, these non-printing control characters must be designated as invisible by
surrounding them with %[ and %]. Multiple pairs of these can occur within the
prompt. For example:
testdb=> \set PROMPT1 '%[%033[1;33;40m%]%n@%/%R%[%033[0m%]%# '
results in a boldfaced (1;) yellow-on-black (33;40) prompt on VT100-compatible,
color-capable terminals.
To insert a percent sign into your prompt, write %%. The default prompts are '%/%R%# '
for prompts 1 and 2, and '>> ' for prompt 3.
Note
This feature was shamelessly plagiarized from tcsh.
Command-Line Editing
psql supports the Readline library for convenient line editing and retrieval. The
command history is automatically saved when psql exits and is reloaded when psql
starts up. Tab-completion is also supported, although the completion logic makes no
claim to be an SQL parser. The queries generated by tab-completion can also interfere
with other SQL commands, e.g., SET TRANSACTION ISOLATION LEVEL. If for some reason you
do not like the tab completion, you can turn it off by putting this in a file named
.inputrc in your home directory:
$if psql
set disable-completion on
$endif
(This is not a psql but a Readline feature. Read its documentation for further
details.)
ENVIRONMENT
COLUMNS
If \pset columns is zero, controls the width for the wrapped format and width for
determining if wide output requires the pager or should be switched to the vertical
format in expanded auto mode.
PGDATABASE
PGHOST
PGPORT
PGUSER
Default connection parameters (see Section 33.14).
PG_COLOR
Specifies whether to use color in diagnostic messages. Possible values are always,
auto and never.
PSQL_EDITOR
EDITOR
VISUAL
Editor used by the \e, \ef, and \ev commands. These variables are examined in the
order listed; the first that is set is used. If none of them is set, the default is to
use vi on Unix systems or notepad.exe on Windows systems.
PSQL_EDITOR_LINENUMBER_ARG
When \e, \ef, or \ev is used with a line number argument, this variable specifies the
command-line argument used to pass the starting line number to the user's editor. For
editors such as Emacs or vi, this is a plus sign. Include a trailing space in the
value of the variable if there needs to be space between the option name and the line
number. Examples:
PSQL_EDITOR_LINENUMBER_ARG='+'
PSQL_EDITOR_LINENUMBER_ARG='--line '
The default is + on Unix systems (corresponding to the default editor vi, and useful
for many other common editors); but there is no default on Windows systems.
PSQL_HISTORY
Alternative location for the command history file. Tilde (~) expansion is performed.
PSQL_PAGER
PAGER
If a query's results do not fit on the screen, they are piped through this command.
Typical values are more or less. Use of the pager can be disabled by setting
PSQL_PAGER or PAGER to an empty string, or by adjusting the pager-related options of
the \pset command. These variables are examined in the order listed; the first that is
set is used. If none of them is set, the default is to use more on most platforms, but
less on Cygwin.
PSQLRC
Alternative location of the user's .psqlrc file. Tilde (~) expansion is performed.
SHELL
Command executed by the \! command.
TMPDIR
Directory for storing temporary files. The default is /tmp.
This utility, like most other PostgreSQL utilities, also uses the environment variables
supported by libpq (see Section 33.14).
FILES
psqlrc and ~/.psqlrc
Unless it is passed an -X option, psql attempts to read and execute commands from the
system-wide startup file (psqlrc) and then the user's personal startup file
(~/.psqlrc), after connecting to the database but before accepting normal commands.
These files can be used to set up the client and/or the server to taste, typically
with \set and SET commands.
The system-wide startup file is named psqlrc and is sought in the installation's
“system configuration” directory, which is most reliably identified by running
pg_config --sysconfdir. By default this directory will be ../etc/ relative to the
directory containing the PostgreSQL executables. The name of this directory can be set
explicitly via the PGSYSCONFDIR environment variable.
The user's personal startup file is named .psqlrc and is sought in the invoking user's
home directory. On Windows, which lacks such a concept, the personal startup file is
named %APPDATA%\postgresql\psqlrc.conf. The location of the user's startup file can be
set explicitly via the PSQLRC environment variable.
Both the system-wide startup file and the user's personal startup file can be made
psql-version-specific by appending a dash and the PostgreSQL major or minor release
number to the file name, for example ~/.psqlrc-9.2 or ~/.psqlrc-9.2.5. The most
specific version-matching file will be read in preference to a non-version-specific
file.
.psql_history
The command-line history is stored in the file ~/.psql_history, or
%APPDATA%\postgresql\psql_history on Windows.
The location of the history file can be set explicitly via the HISTFILE psql variable
or the PSQL_HISTORY environment variable.
NOTES
• psql works best with servers of the same or an older major version. Backslash commands
are particularly likely to fail if the server is of a newer version than psql itself.
However, backslash commands of the \d family should work with servers of versions back
to 7.4, though not necessarily with servers newer than psql itself. The general
functionality of running SQL commands and displaying query results should also work
with servers of a newer major version, but this cannot be guaranteed in all cases.
If you want to use psql to connect to several servers of different major versions, it
is recommended that you use the newest version of psql. Alternatively, you can keep
around a copy of psql from each major version and be sure to use the version that
matches the respective server. But in practice, this additional complication should
not be necessary.
• Before PostgreSQL 9.6, the -c option implied -X (--no-psqlrc); this is no longer the
case.
• Before PostgreSQL 8.4, psql allowed the first argument of a single-letter backslash
command to start directly after the command, without intervening whitespace. Now, some
whitespace is required.
NOTES FOR WINDOWS USERS
psql is built as a “console application”. Since the Windows console windows use a
different encoding than the rest of the system, you must take special care when using
8-bit characters within psql. If psql detects a problematic console code page, it will
warn you at startup. To change the console code page, two things are necessary:
• Set the code page by entering cmd.exe /c chcp 1252. (1252 is a code page that is
appropriate for German; replace it with your value.) If you are using Cygwin, you can
put this command in /etc/profile.
• Set the console font to Lucida Console, because the raster font does not work with the
ANSI code page.
EXAMPLES
The first example shows how to spread a command over several lines of input. Notice the
changing prompt:
testdb=> CREATE TABLE my_table (
testdb(> first integer not null default 0,
testdb(> second text)
testdb-> ;
CREATE TABLE
Now look at the table definition again:
testdb=> \d my_table
Table "public.my_table"
Column | Type | Collation | Nullable | Default
--------+---------+-----------+----------+---------
first | integer | | not null | 0
second | text | | |
Now we change the prompt to something more interesting:
testdb=> \set PROMPT1 '%n@%m %~%R%# '
peter@localhost testdb=>
Let's assume you have filled the table with data and want to take a look at it:
peter@localhost testdb=> SELECT * FROM my_table;
first | second
-------+--------
1 | one
2 | two
3 | three
4 | four
(4 rows)
You can display tables in different ways by using the \pset command:
peter@localhost testdb=> \pset border 2
Border style is 2.
peter@localhost testdb=> SELECT * FROM my_table;
+-------+--------+
| first | second |
+-------+--------+
| 1 | one |
| 2 | two |
| 3 | three |
| 4 | four |
+-------+--------+
(4 rows)
peter@localhost testdb=> \pset border 0
Border style is 0.
peter@localhost testdb=> SELECT * FROM my_table;
first second
----- ------
1 one
2 two
3 three
4 four
(4 rows)
peter@localhost testdb=> \pset border 1
Border style is 1.
peter@localhost testdb=> \pset format csv
Output format is csv.
peter@localhost testdb=> \pset tuples_only
Tuples only is on.
peter@localhost testdb=> SELECT second, first FROM my_table;
one,1
two,2
three,3
four,4
peter@localhost testdb=> \pset format unaligned
Output format is unaligned.
peter@localhost testdb=> \pset fieldsep '\t'
Field separator is " ".
peter@localhost testdb=> SELECT second, first FROM my_table;
one 1
two 2
three 3
four 4
Alternatively, use the short commands:
peter@localhost testdb=> \a \t \x
Output format is aligned.
Tuples only is off.
Expanded display is on.
peter@localhost testdb=> SELECT * FROM my_table;
-[ RECORD 1 ]-
first | 1
second | one
-[ RECORD 2 ]-
first | 2
second | two
-[ RECORD 3 ]-
first | 3
second | three
-[ RECORD 4 ]-
first | 4
second | four
When suitable, query results can be shown in a crosstab representation with the
\crosstabview command:
testdb=> SELECT first, second, first > 2 AS gt2 FROM my_table;
first | second | gt2
-------+--------+-----
1 | one | f
2 | two | f
3 | three | t
4 | four | t
(4 rows)
testdb=> \crosstabview first second
first | one | two | three | four
-------+-----+-----+-------+------
1 | f | | |
2 | | f | |
3 | | | t |
4 | | | | t
(4 rows)
This second example shows a multiplication table with rows sorted in reverse numerical
order and columns with an independent, ascending numerical order.
testdb=> SELECT t1.first as "A", t2.first+100 AS "B", t1.first*(t2.first+100) as "AxB",
testdb(> row_number() over(order by t2.first) AS ord
testdb(> FROM my_table t1 CROSS JOIN my_table t2 ORDER BY 1 DESC
testdb(> \crosstabview "A" "B" "AxB" ord
A | 101 | 102 | 103 | 104
---+-----+-----+-----+-----
4 | 404 | 408 | 412 | 416
3 | 303 | 306 | 309 | 312
2 | 202 | 204 | 206 | 208
1 | 101 | 102 | 103 | 104
(4 rows)