psql — PostgreSQL interactive terminal
psql [option...] [dbname
[username]]
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.
-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 54.2.2.1
for more details about how the server handles multi-query strings.)
If having several commands executed in one transaction is not desired,
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
< . In general,
both will do what you expect, but using filename-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 (see the section called “Command-Line Editing” below).
-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.
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. If any of the commands fails and the variable
ON_ERROR_STOP was set, a
ROLLBACK command is sent instead. 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.
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.
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
database 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 database 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
Windows. 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 database user name is your
operating-system user name. Once the database user name is determined, it
is used as the default database name.
Note that you cannot
just connect to any database under any database 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 32.15.) It is also convenient to have a
~/.pgpass file to avoid regularly having to type in
passwords. See Section 32.16 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 32.18. See Section 32.1.2 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.
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 (18.3)
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 and
NOTIFY.
While C-style block comments are passed to the server for processing and removal, SQL-standard comments are removed by psql.
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 below.
The forms :' 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.
variable_name}
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 : where
variable_namevariable_name is a psql variable name
are replaced by the variable's value. Also, appearances of
:' 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.
variable_name'
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.
Many of the meta-commands also allow x to be appended
as an option. This will cause the results to be displayed in expanded
mode, as if \x or \pset expanded
had been used.
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.
\bind [ parameter ] ... #
Sets query parameters for the next query execution, with the
specified parameters passed for any parameter placeholders
($1 etc.).
Example:
INSERT INTO tbl1 VALUES ($1, $2) \bind 'first value' 'second value' \g
This also works for query-execution commands besides
\g, such as \gx and
\gset.
This command causes the extended query protocol (see Section 54.1.2) to be used, unlike normal psql operation, which uses the simple query protocol. So this command can be useful to test the extended query protocol from psql. (The extended query protocol is used even if the query has no parameters and this command specifies zero parameters.) This command affects only the next query executed; all subsequent queries will use the simple query protocol by default.
\bind_named statement_name [ parameter ] ... #
\bind_named is equivalent to \bind,
except that it takes the name of an existing prepared statement as
first parameter. An empty string denotes the unnamed prepared
statement.
Example:
INSERT INTO tbls1 VALUES ($1, $2) \parse stmt1 \bind_named stmt1 'first value' 'second value' \g
This command causes the extended query protocol (see Section 54.1.2) to be used, unlike normal psql operation, which uses the simple query protocol. So this command can be useful to test the extended query protocol from psql.
\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 32.1.1. 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, the old connection is closed
and an error is reported. That may or may not terminate the
script; if it does not, all database-accessing commands will fail
until another \connect command is successfully
executed. 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.
Note that whenever a \connect command attempts
to re-use parameters, the values re-used are those of the last
successful connection, not of any failed attempts made subsequently.
However, in the case of a
non-interactive \connect failure, no parameters
are allowed to be re-used later, since the script would likely be
expecting the values from the failed \connect
to be re-used.
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 . (The name of
this command derives from “caption”, as it was
previously only used to set the caption in an
HTML table.)
title
\cd [ directory ] #
Changes the current working directory to
directory. Without argument, changes
to the current user's home directory. For details on how home
directories are found, see Section 32.16.
To print your current working directory, use \! pwd.
\close_prepared prepared_statement_name #Closes the specified prepared statement. An empty string denotes the unnamed prepared statement. If no prepared statement exists with this name, the operation is a no-op.
Example:
SELECT $1 \parse stmt1 \close_prepared stmt1
This command causes the extended query protocol to be used, unlike normal psql operation, which uses the simple query protocol. So this command can be useful to test the extended query protocol from psql.
\conninfo #Outputs information about the current database connection, including SSL-related information if SSL is in use.
Note that the Client User field shows
the user at the time of connection, while the
Superuser field indicates whether
the current user (in the current execution context) has
superuser privileges. These users are usually the same, but they can
differ, for example, if the current user was changed with the
SET ROLE command.
\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
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 a line containing
only \.
is read or the stream reaches EOF. This option is useful
for populating tables in-line within an SQL script file.
For \copy ... to stdout, output is sent to the same place
as psql command output, and
the COPY 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 count\o
option, write from pstdin or to pstdout.
The syntax of this command is similar to that of the
SQL COPY
command. All options other than the data source/destination are
as specified for COPY.
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.
Another way to obtain the same result as \copy
... to is to use the SQL COPY
... TO STDOUT command and terminate it
with \g
or filename\g |.
Unlike program\copy, this method allows the command to
span multiple lines; also, variable interpolation and backquote
expansion can be used.
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.
\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[Sx+] [ 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 and the
access method name
if the relation has an access method.
By default, only user-created objects are shown; supply a
pattern or the S modifier to include system
objects.
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.
As with many other commands, if x is appended to
the command name, the results are displayed in expanded mode, but note
that this only applies when \d is used without a
pattern argument, and
the x modifier cannot appear immediately after the
\d (because \dx is a different
command); the x modifier may only appear after an
S or + modifier. For example,
\d+x is equivalent to \dtvmsE+x
and will show a list of all relations in expanded mode.
\da[Sx] [ 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.
If x is appended to the command name, the results
are displayed in expanded mode.
\dA[x+] [ pattern ] #
Lists access methods. If pattern is specified, only access
methods whose names match the pattern are shown.
If x is appended to the command name, the results
are displayed in expanded mode.
If + is appended to the command name, each access
method is listed with its associated handler function and description.
\dAc[x+]
[access-method-pattern
[input-type-pattern]]
#
Lists operator classes
(see Section 36.16.1).
If access-method-pattern
is specified, only operator classes associated with access methods whose
names match that pattern are listed.
If input-type-pattern
is specified, only operator classes associated with input types whose
names match that pattern are listed.
If x is appended to the command name, the results
are displayed in expanded mode.
If + is appended to the command name, each operator
class is listed with its associated operator family and owner.
\dAf[x+]
[access-method-pattern
[input-type-pattern]]
#
Lists operator families
(see Section 36.16.5).
If access-method-pattern
is specified, only operator families associated with access methods whose
names match that pattern are listed.
If input-type-pattern
is specified, only operator families associated with input types whose
names match that pattern are listed.
If x is appended to the command name, the results
are displayed in expanded mode.
If + is appended to the command name, each operator
family is listed with its owner.
\dAo[x+]
[access-method-pattern
[operator-family-pattern]]
#
Lists operators associated with operator families
(see Section 36.16.2).
If access-method-pattern
is specified, only members of operator families associated with access
methods whose names match that pattern are listed.
If operator-family-pattern
is specified, only members of operator families whose names match that
pattern are listed.
If x is appended to the command name, the results
are displayed in expanded mode.
If + is appended to the command name, each operator
is listed with its sort operator family (if it is an ordering operator),
and whether its underlying function is leakproof.
\dAp[x+]
[access-method-pattern
[operator-family-pattern]]
#
Lists support functions associated with operator families
(see Section 36.16.3).
If access-method-pattern
is specified, only functions of operator families associated with
access methods whose names match that pattern are listed.
If operator-family-pattern
is specified, only functions of operator families whose names match
that pattern are listed.
If x is appended to the command name, the results
are displayed in expanded mode.
If + is appended to the command name, functions are
displayed verbosely, with their actual parameter lists.
\db[x+] [ pattern ] #
Lists tablespaces. If pattern
is specified, only tablespaces whose names match the pattern are shown.
If x is appended to the command name, the results
are displayed in expanded mode.
If + is appended to the command name, each tablespace
is listed with its associated options, on-disk size, permissions and
description.
\dc[Sx+] [ 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 x is appended to the command name, the results
are displayed in expanded mode.
If + is appended to the command name, each object
is listed with its associated description.
\dconfig[x+] [ pattern ] #
Lists server configuration parameters and their values.
If pattern is specified,
only parameters whose names match the pattern are listed. Without
a pattern, only
parameters that are set to non-default values are listed.
(Use \dconfig * to see all parameters.)
If x is appended to the command name, the results
are displayed in expanded mode.
If + is appended to the command name, each
parameter is listed with its data type, context in which the
parameter can be set, and access privileges (if non-default access
privileges have been granted).
\dC[x+] [ pattern ] #
Lists type casts.
If pattern
is specified, only casts whose source or target types match the
pattern are listed.
If x is appended to the command name, the results
are displayed in expanded mode.
If + is appended to the command name, additional
information about each cast is shown, including whether its underlying
function is leakproof, and the cast's description.
\dd[Sx] [ 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.
If x is appended to the command name, the results
are displayed in expanded mode.
Descriptions for objects can be created with the COMMENT
SQL command.
\dD[Sx+] [ 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 x is appended to the command name, the results
are displayed in expanded mode.
If + is appended to the command name, each object
is listed with its associated permissions and description.
\ddp[x] [ 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.
If x is appended to the command name, the results
are displayed in expanded mode.
The ALTER DEFAULT
PRIVILEGES command is used to set default access
privileges. The meaning of the privilege display is explained in
Section 5.8.
\dE[Sx+] [ pattern ]\di[Sx+] [ pattern ]\dm[Sx+] [ pattern ]\ds[Sx+] [ pattern ]\dt[Sx+] [ pattern ]\dv[Sx+] [ 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, \dti lists
tables and indexes.
If x is appended to the command name, the results
are displayed in expanded mode.
If + is
appended to the command name, each object is listed with its
persistence status (permanent, temporary, or unlogged),
physical size on disk, and 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[x+] [ pattern ] #
Lists foreign servers (mnemonic: “external
servers”).
If pattern is
specified, only those servers whose name matches the pattern
are listed.
If x is appended to the command name, the results
are displayed in expanded mode.
If + is appended to the command name, a
full description of each server is shown, including the
server's access privileges, type, version, options, and description.
\det[x+] [ 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 x is appended to the command name, the results
are displayed in expanded mode.
If + is appended to the command name,
generic options and the foreign table description
are also displayed.
\deu[x+] [ pattern ] #
Lists user mappings (mnemonic: “external
users”).
If pattern is
specified, only those mappings whose user names match the
pattern are listed.
If x is appended to the command name, the results
are displayed in expanded mode.
If + is appended to the command name,
additional information about each mapping is shown.
\deu+ might also display the user name and
password of the remote user, so care should be taken not to
disclose them.
\dew[x+] [ 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 x is appended to the command name, the results
are displayed in expanded mode.
If + is appended to the command name,
the access privileges, options, and description of the
foreign-data wrapper are also shown.
\df[anptwSx+] [ pattern [ arg_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.
Any additional arguments are type-name patterns, which are matched
to the type names of the first, second, and so on arguments of the
function. (Matching functions can have more arguments than what
you specify. To prevent that, write a dash - as
the last arg_pattern.)
By default, only user-created
objects are shown; supply a pattern or the S
modifier to include system objects.
If x is appended to the command name, the results
are displayed in expanded mode.
If + is appended to the command name, additional information
about each function is shown, including volatility,
parallel safety, owner, security classification, whether it is
leakproof, access privileges, language, internal name (for C and
internal functions only), and description.
Source code for a specific function can be seen
using \sf.
\dF[x+] [ pattern ] #
Lists text search configurations.
If pattern is specified,
only configurations whose names match the pattern are shown.
If x is appended to the command name, the results
are displayed in expanded mode.
If + is appended to the command name, a full description of
each configuration is shown, including the underlying text search
parser and the dictionary list for each parser token type.
\dFd[x+] [ pattern ] #
Lists text search dictionaries.
If pattern is specified,
only dictionaries whose names match the pattern are shown.
If x is appended to the command name, the results
are displayed in expanded mode.
If + is appended to the command name, additional information
is shown about each selected dictionary, including the underlying
text search template and the option values.
\dFp[x+] [ pattern ] #
Lists text search parsers.
If pattern is specified,
only parsers whose names match the pattern are shown.
If x is appended to the command name, the results
are displayed in expanded mode.
If + is appended to the command name, a full description of
each parser is shown, including the underlying functions and the
list of recognized token types.
\dFt[x+] [ pattern ] #
Lists text search templates.
If pattern is specified,
only templates whose names match the pattern are shown.
If x is appended to the command name, the results
are displayed in expanded mode.
If + is appended to the command name, additional information
is shown about each template, including the underlying function names.
\dg[Sx+] [ 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 x is appended to the command name, the results
are displayed in expanded mode.
If + is appended to the command name, additional information
is shown about each role; currently this adds the comment for each
role.
\dl[x+] #
This is an alias for \lo_list, which shows a
list of large objects.
If x is appended to the command name, the results
are displayed in expanded mode.
If + is appended to the command name,
each large object is listed with its associated permissions,
if any.
\dL[Sx+] [ 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 x is appended to the command name, the results
are displayed in expanded mode.
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[Sx+] [ 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 x is appended to the command name, the results
are displayed in expanded mode.
If + is appended to the command name, each object
is listed with its associated permissions and description, if any.
\do[Sx+] [ pattern [ arg_pattern [ arg_pattern ] ] ] #
Lists operators with their operand and result types.
If pattern is
specified, only operators whose names match the pattern are listed.
If one arg_pattern is
specified, only prefix operators whose right argument's type name
matches that pattern are listed.
If two arg_patterns
are specified, only binary operators whose argument type names match
those patterns are listed. (Alternatively, write -
for the unused argument of a unary operator.)
By default, only user-created objects are shown; supply a
pattern or the S modifier to include system
objects.
If x is appended to the command name, the results
are displayed in expanded mode.
If + is appended to the command name,
additional information about each operator is shown, including
the name of the underlying function, and whether it is leakproof.
\dO[Sx+] [ 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 x is appended to the command name, the results
are displayed in expanded mode.
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[Sx] [ 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. By default only user-created objects are shown;
supply a pattern or the S modifier to include
system objects.
If x is appended to the command name, the results
are displayed in expanded mode.
The GRANT and
REVOKE
commands are used to set access privileges. The meaning of the
privilege display is explained in
Section 5.8.
\dP[itnx+] [ 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 x is appended to the command name, the results
are displayed in expanded mode.
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[x] [ 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.
If x is appended to the command name, the results
are displayed in expanded mode.
The ALTER ROLE and
ALTER DATABASE
commands are used to define per-role and per-database configuration
settings.
\drg[Sx] [ pattern ] #
Lists information about each granted role membership, including
assigned options (ADMIN,
INHERIT and/or SET) and grantor.
See the GRANT
command for information about role memberships.
By default, only grants to user-created roles are shown; supply the
S modifier to include system roles.
If pattern is specified,
only grants to those roles whose names match the pattern are listed.
If x is appended to the command name, the results
are displayed in expanded mode.
\dRp[x+] [ pattern ] #
Lists replication publications.
If pattern is
specified, only those publications whose names match the pattern are
listed.
If x is appended to the command name, the results
are displayed in expanded mode.
If + is appended to the command name, the tables and
schemas associated with each publication are shown as well.
\dRs[x+] [ pattern ] #
Lists replication subscriptions.
If pattern is
specified, only those subscriptions whose names match the pattern are
listed.
If x is appended to the command name, the results
are displayed in expanded mode.
If + is appended to the command name, additional
properties of the subscriptions are shown.
\dT[Sx+] [ pattern ] #
Lists data types.
If pattern is
specified, only types whose names match the pattern are listed.
If x is appended to the command name, the results
are displayed in expanded mode.
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[Sx+] [ 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 x is appended to the command name, the results
are displayed in expanded mode.
If + is appended to the command name, additional information
is shown about each role; currently this adds the comment for each
role.
\dx[x+] [ pattern ] #
Lists installed extensions.
If pattern
is specified, only those extensions whose names match the pattern
are listed.
If x is appended to the command name, the results
are displayed in expanded mode.
If + is appended to the command name, all the objects belonging
to each matching extension are listed.
\dX[x] [ pattern ] #
Lists extended statistics.
If pattern
is specified, only those extended statistics whose names match the
pattern are listed.
If x is appended to the command name, the results
are displayed in expanded mode.
The status of each kind of extended statistics is shown in a column
named after its statistic kind (e.g. Ndistinct).
defined means that it was requested when creating
the statistics, and NULL means it wasn't requested.
You can use pg_stats_ext if you'd like to
know whether ANALYZE
was run and statistics are available to the planner.
\dy[x+] [ pattern ] #
Lists event triggers.
If pattern
is specified, only those event triggers whose names match the pattern
are listed.
If x is appended to the command name, the results
are displayed in expanded mode.
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.
If you edit a file or the previous query, and you quit the editor without
modifying the file, the query buffer is cleared.
Otherwise, the new contents of the query buffer are 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 and removed from
the query buffer. Whatever remains in the query buffer is
redisplayed. 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.
See Environment, below, for how to configure and customize your editor.
\echo text [ ... ] #Prints the evaluated arguments to standard output, separated by spaces 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 (nor is the first argument).
If you use the \o command to redirect your
query output you might wish to use \qecho
instead of this command. See also \warn.
\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.
If you quit the editor without saving, the statement is discarded.
If you save and exit the editor, the updated command is executed immediately
if you added a semicolon to it. Otherwise it is redisplayed;
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.
See Environment, below, 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.
If you quit the editor without saving, the statement is discarded.
If you save and exit the editor, the updated command is executed immediately
if you added a semicolon to it. Otherwise it is redisplayed;
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 [ (option=value [...]) ] [ filename ]\g [ (option=value [...]) ] [ |command ] #Sends the current query buffer to the server for execution.
If parentheses appear after \g, they surround a
space-separated list
of option=value
formatting-option clauses, which are interpreted in the same way
as \pset
option
value commands, but take
effect only for the duration of this query. In this list, spaces are
not allowed around = signs, but are required
between option clauses.
If =value
is omitted, the
named option is changed
in the same way as for
\pset option
with no explicit value.
If a filename
or |command
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 any arguments is essentially equivalent to a semicolon.
With arguments, \g provides
a “one-shot” alternative to the \o
command, and additionally allows one-shot adjustments of the
output formatting options normally set by \pset.
When the last argument begins with |, 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.
\getenv psql_var env_var #
Gets the value of the environment
variable env_var
and assigns it to the psql
variable psql_var.
If env_var is
not defined in the psql process's
environment, psql_var
is not changed. Example:
=>\getenv home HOME=>\echo :home/home/postgres
\gexec #
Sends the current query buffer to the server, then treats
each column of each row of the query's output (if any) as an 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->\gexecCREATE 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 below). 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 :var2hello 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_var2hello 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 [ (option=value [...]) ] [ filename ]\gx [ (option=value [...]) ] [ |command ] #
\gx is equivalent to \g, except
that it forces expanded output mode for this query, as
if expanded=on were included in the list of
\pset options. See also \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.
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.
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[x+] or \list[x+] [ 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 x is appended to the command name, the results
are displayed in expanded mode.
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.
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[x+] #
Shows a list of all PostgreSQL
large objects currently stored in the database,
along with any comments provided for them.
If x is appended to the command name, the results
are displayed in expanded mode.
If + is appended to the command name,
each large object is listed with its associated permissions,
if any.
\lo_unlink loid #
Deletes the large object with OID
loid from the
database.
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.
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.
\parse statement_name #Creates a prepared statement from the current query buffer, based on the name of a destination prepared-statement object. An empty string denotes the unnamed prepared statement.
Example:
SELECT $1 \parse stmt1
This command causes the extended query protocol to be used, unlike normal psql operation, which uses the simple query protocol. A Parse (F) message will be issued by this command so it can be useful to test the extended query protocol from psql. This command affects only the next query executed; all subsequent queries will use the simple query protocol by default.
\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 ( count).
If n rows)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