2 doc/src/sgml/ref/psql-ref.sgml
3 PostgreSQL documentation
6 <refentry id="APP-PSQL">
8 <refentrytitle><application>psql</application></refentrytitle>
9 <manvolnum>1</manvolnum>
10 <refmiscinfo>Application</refmiscinfo>
14 <refname><application>psql</application></refname>
16 <productname>PostgreSQL</productname> interactive terminal
20 <indexterm zone="app-psql">
21 <primary>psql</primary>
26 <command>psql</command>
27 <arg rep="repeat"><replaceable class="parameter">option</replaceable></arg>
28 <arg choice="opt"><replaceable class="parameter">dbname</replaceable>
29 <arg choice="opt"><replaceable class="parameter">username</replaceable></arg></arg>
34 <title>Description</title>
37 <application>psql</application> is a terminal-based front-end to
38 <productname>PostgreSQL</productname>. It enables you to type in
39 queries interactively, issue them to
40 <productname>PostgreSQL</productname>, and see the query results.
41 Alternatively, input can be from a file. In addition, it provides a
42 number of meta-commands and various shell-like features to
43 facilitate writing scripts and automating a wide variety of tasks.
47 <refsect1 id="R1-APP-PSQL-3">
48 <title>Options</title>
52 <term><option>-a</></term>
53 <term><option>--echo-all</></term>
56 Print all input lines to standard output as they are read. This is more
57 useful for script processing than interactive mode. This is
58 equivalent to setting the variable <varname>ECHO</varname> to
59 <literal>all</literal>.
65 <term><option>-A</></term>
66 <term><option>--no-align</></term>
69 Switches to unaligned output mode. (The default output mode is
76 <term><option>-c <replaceable class="parameter">command</replaceable></></term>
77 <term><option>--command=<replaceable class="parameter">command</replaceable></></term>
80 Specifies that <application>psql</application> is to execute one
81 command string, <replaceable class="parameter">command</replaceable>,
82 and then exit. This is useful in shell scripts. Start-up files
83 (<filename>psqlrc</filename> and <filename>~/.psqlrc</filename>) are
84 ignored with this option.
86 <para><replaceable class="parameter">command</replaceable> must be either
87 a command string that is completely parsable by the server (i.e.,
88 it contains no <application>psql</application>-specific features),
89 or a single backslash command. Thus you cannot mix
90 <acronym>SQL</acronym> and <application>psql</application>
91 meta-commands with this option. To achieve that, you could
92 pipe the string into <application>psql</application>, like
93 this: <literal>echo '\x \\ SELECT * FROM foo;' | psql</literal>.
94 (<literal>\\</> is the separator meta-command.)
97 If the command string contains multiple SQL commands, they are
98 processed in a single transaction, unless there are explicit
99 <command>BEGIN</>/<command>COMMIT</> commands included in the
100 string to divide it into multiple transactions. This is
101 different from the behavior when the same string is fed to
102 <application>psql</application>'s standard input.
108 <term><option>-d <replaceable class="parameter">dbname</replaceable></></term>
109 <term><option>--dbname=<replaceable class="parameter">dbname</replaceable></></term>
112 Specifies the name of the database to connect to. This is
113 equivalent to specifying <replaceable
114 class="parameter">dbname</replaceable> as the first non-option
115 argument on the command line.
118 If this parameter contains an <symbol>=</symbol> sign or starts
119 with a valid <acronym>URI</acronym> prefix
120 (<literal>postgresql://</literal>
121 or <literal>postgres://</literal>), it is treated as a
122 <parameter>conninfo</parameter> string. See <xref linkend="libpq-connect"> for more information.
128 <term><option>-e</></term>
129 <term><option>--echo-queries</></term>
132 Copy all SQL commands sent to the server to standard output as well.
134 to setting the variable <varname>ECHO</varname> to
135 <literal>queries</literal>.
141 <term><option>-E</></term>
142 <term><option>--echo-hidden</></term>
145 Echo the actual queries generated by <command>\d</command> and other backslash
146 commands. You can use this to study <application>psql</application>'s
147 internal operations. This is equivalent to
148 setting the variable <varname>ECHO_HIDDEN</varname> from within
149 <application>psql</application>.
155 <term><option>-f <replaceable class="parameter">filename</replaceable></></term>
156 <term><option>--file=<replaceable class="parameter">filename</replaceable></></term>
159 Use the file <replaceable class="parameter">filename</replaceable>
160 as the source of commands instead of reading commands interactively.
161 After the file is processed, <application>psql</application>
162 terminates. This is in many ways equivalent to the meta-command
163 <command>\i</command>.
167 If <replaceable>filename</replaceable> is <literal>-</literal>
168 (hyphen), then standard input is read.
172 Using this option is subtly different from writing <literal>psql
174 class="parameter">filename</replaceable></literal>. In general,
175 both will do what you expect, but using <literal>-f</literal>
176 enables some nice features such as error messages with line
177 numbers. There is also a slight chance that using this option will
178 reduce the start-up overhead. On the other hand, the variant using
179 the shell's input redirection is (in theory) guaranteed to yield
180 exactly the same output you would have received had you entered
187 <term><option>-F <replaceable class="parameter">separator</replaceable></></term>
188 <term><option>--field-separator=<replaceable class="parameter">separator</replaceable></></term>
191 Use <replaceable class="parameter">separator</replaceable> as the
192 field separator for unaligned output. This is equivalent to
193 <command>\pset fieldsep</command> or <command>\f</command>.
199 <term><option>-h <replaceable class="parameter">hostname</replaceable></></term>
200 <term><option>--host=<replaceable class="parameter">hostname</replaceable></></term>
203 Specifies the host name of the machine on which the
204 server is running. If the value begins
205 with a slash, it is used as the directory for the Unix-domain
212 <term><option>-H</></term>
213 <term><option>--html</></term>
216 Turn on <acronym>HTML</acronym> tabular output. This is
217 equivalent to <literal>\pset format html</literal> or the
218 <command>\H</command> command.
224 <term><option>-l</></term>
225 <term><option>--list</></term>
228 List all available databases, then exit. Other non-connection
229 options are ignored. This is similar to the meta-command
230 <command>\list</command>.
236 <term><option>-L <replaceable class="parameter">filename</replaceable></></term>
237 <term><option>--log-file=<replaceable class="parameter">filename</replaceable></></term>
240 Write all query output into file <replaceable
241 class="parameter">filename</replaceable>, in addition to the
242 normal output destination.
248 <term><option>-n</></term>
249 <term><option>--no-readline</></term>
252 Do not use readline for line editing and do not use the history.
253 This can be useful to turn off tab expansion when cutting and pasting.
259 <term><option>-o <replaceable class="parameter">filename</replaceable></></term>
260 <term><option>--output=<replaceable class="parameter">filename</replaceable></></term>
263 Put all query output into file <replaceable
264 class="parameter">filename</replaceable>. This is equivalent to
265 the command <command>\o</command>.
271 <term><option>-p <replaceable class="parameter">port</replaceable></></term>
272 <term><option>--port=<replaceable class="parameter">port</replaceable></></term>
275 Specifies the TCP port or the local Unix-domain
276 socket file extension on which the server is listening for
277 connections. Defaults to the value of the <envar>PGPORT</envar>
278 environment variable or, if not set, to the port specified at
279 compile time, usually 5432.
285 <term><option>-P <replaceable class="parameter">assignment</replaceable></></term>
286 <term><option>--pset=<replaceable class="parameter">assignment</replaceable></></term>
289 Specifies printing options, in the style of
290 <command>\pset</command>. Note that here you
291 have to separate name and value with an equal sign instead of a
292 space. For example, to set the output format to LaTeX, you could write
293 <literal>-P format=latex</literal>.
299 <term><option>-q</></term>
300 <term><option>--quiet</></term>
303 Specifies that <application>psql</application> should do its work
304 quietly. By default, it prints welcome messages and various
305 informational output. If this option is used, none of this
306 happens. This is useful with the <option>-c</option> option.
307 Within <application>psql</application> you can also set the
308 <varname>QUIET</varname> variable to achieve the same effect.
314 <term><option>-R <replaceable class="parameter">separator</replaceable></></term>
315 <term><option>--record-separator=<replaceable class="parameter">separator</replaceable></></term>
318 Use <replaceable class="parameter">separator</replaceable> as the
319 record separator for unaligned output. This is equivalent to the
320 <command>\pset recordsep</command> command.
326 <term><option>-s</></term>
327 <term><option>--single-step</></term>
330 Run in single-step mode. That means the user is prompted before
331 each command is sent to the server, with the option to cancel
332 execution as well. Use this to debug scripts.
338 <term><option>-S</></term>
339 <term><option>--single-line</></term>
342 Runs in single-line mode where a newline terminates an SQL command, as a
348 This mode is provided for those who insist on it, but you are not
349 necessarily encouraged to use it. In particular, if you mix
350 <acronym>SQL</acronym> and meta-commands on a line the order of
351 execution might not always be clear to the inexperienced user.
358 <term><option>-t</></term>
359 <term><option>--tuples-only</></term>
362 Turn off printing of column names and result row count footers,
363 etc. This is equivalent to the <command>\t</command> command.
369 <term><option>-T <replaceable class="parameter">table_options</replaceable></></term>
370 <term><option>--table-attr=<replaceable class="parameter">table_options</replaceable></></term>
373 Specifies options to be placed within the
374 <acronym>HTML</acronym> <sgmltag>table</sgmltag> tag. See
375 <command>\pset</command> for details.
381 <term><option>-U <replaceable class="parameter">username</replaceable></></term>
382 <term><option>--username=<replaceable class="parameter">username</replaceable></></term>
385 Connect to the database as the user <replaceable
386 class="parameter">username</replaceable> instead of the default.
387 (You must have permission to do so, of course.)
393 <term><option>-v <replaceable class="parameter">assignment</replaceable></></term>
394 <term><option>--set=<replaceable class="parameter">assignment</replaceable></></term>
395 <term><option>--variable=<replaceable class="parameter">assignment</replaceable></></term>
398 Perform a variable assignment, like the <command>\set</command>
399 meta-command. Note that you must separate name and value, if
400 any, by an equal sign on the command line. To unset a variable,
401 leave off the equal sign. To set a variable with an empty value,
402 use the equal sign but leave off the value. These assignments are
403 done during a very early stage of start-up, so variables reserved
404 for internal purposes might get overwritten later.
410 <term><option>-V</></term>
411 <term><option>--version</></term>
414 Print the <application>psql</application> version and exit.
420 <term><option>-w</></term>
421 <term><option>--no-password</></term>
424 Never issue a password prompt. If the server requires password
425 authentication and a password is not available by other means
426 such as a <filename>.pgpass</filename> file, the connection
427 attempt will fail. This option can be useful in batch jobs and
428 scripts where no user is present to enter a password.
432 Note that this option will remain set for the entire session,
433 and so it affects uses of the meta-command
434 <command>\connect</command> as well as the initial connection attempt.
440 <term><option>-W</></term>
441 <term><option>--password</></term>
444 Force <application>psql</application> to prompt for a
445 password before connecting to a database.
449 This option is never essential, since <application>psql</application>
450 will automatically prompt for a password if the server demands
451 password authentication. However, <application>psql</application>
452 will waste a connection attempt finding out that the server wants a
453 password. In some cases it is worth typing <option>-W</> to avoid
454 the extra connection attempt.
458 Note that this option will remain set for the entire session,
459 and so it affects uses of the meta-command
460 <command>\connect</command> as well as the initial connection attempt.
466 <term><option>-x</></term>
467 <term><option>--expanded</></term>
470 Turn on the expanded table formatting mode. This is equivalent to the
471 <command>\x</command> command.
477 <term><option>-X,</></term>
478 <term><option>--no-psqlrc</></term>
481 Do not read the start-up file (neither the system-wide
482 <filename>psqlrc</filename> file nor the user's
483 <filename>~/.psqlrc</filename> file).
489 <term><option>-z</option></term>
490 <term><option>--field-separator-zero</option></term>
493 Set the field separator for unaligned output to a zero byte.
499 <term><option>-0</option></term>
500 <term><option>--record-separator-zero</option></term>
503 Set the record separator for unaligned output to a zero byte. This is
504 useful for interfacing, for example, with <literal>xargs -0</literal>.
510 <term><option>-1</option></term>
511 <term><option>--single-transaction</option></term>
514 When <application>psql</application> executes a script with the
515 <option>-f</> option, adding this option wraps
516 <command>BEGIN</>/<command>COMMIT</> around the script to execute it
517 as a single transaction. This ensures that either all the commands
518 complete successfully, or no changes are applied.
522 If the script itself uses <command>BEGIN</>, <command>COMMIT</>,
523 or <command>ROLLBACK</>, this option will not have the desired
525 Also, if the script contains any command that cannot be executed
526 inside a transaction block, specifying this option will cause that
527 command (and hence the whole transaction) to fail.
533 <term><option>-?</></term>
534 <term><option>--help</></term>
537 Show help about <application>psql</application> command line
548 <title>Exit Status</title>
551 <application>psql</application> returns 0 to the shell if it
552 finished normally, 1 if a fatal error of its own occurs (e.g. out of memory,
553 file not found), 2 if the connection to the server went bad
554 and the session was not interactive, and 3 if an error occurred in a
555 script and the variable <varname>ON_ERROR_STOP</varname> was set.
563 <refsect2 id="R2-APP-PSQL-connecting">
564 <title>Connecting to a Database</title>
567 <application>psql</application> is a regular
568 <productname>PostgreSQL</productname> client application. In order
569 to connect to a database you need to know the name of your target
570 database, the host name and port number of the server, and what user
571 name you want to connect as. <application>psql</application> can be
572 told about those parameters via command line options, namely
573 <option>-d</option>, <option>-h</option>, <option>-p</option>, and
574 <option>-U</option> respectively. If an argument is found that does
575 not belong to any option it will be interpreted as the database name
576 (or the user name, if the database name is already given). Not all
577 of these options are required; there are useful defaults. If you omit the host
578 name, <application>psql</> will connect via a Unix-domain socket
579 to a server on the local host, or via TCP/IP to <literal>localhost</> on
580 machines that don't have Unix-domain sockets. The default port number is
581 determined at compile time.
582 Since the database server uses the same default, you will not have
583 to specify the port in most cases. The default user name is your
584 Unix user name, as is the default database name. Note that you cannot
585 just connect to any database under any user name. Your database
586 administrator should have informed you about your access rights.
590 When the defaults aren't quite right, you can save yourself
591 some typing by setting the environment variables
592 <envar>PGDATABASE</envar>, <envar>PGHOST</envar>,
593 <envar>PGPORT</envar> and/or <envar>PGUSER</envar> to appropriate
594 values. (For additional environment variables, see <xref
595 linkend="libpq-envars">.) It is also convenient to have a
596 <filename>~/.pgpass</> file to avoid regularly having to type in
597 passwords. See <xref linkend="libpq-pgpass"> for more information.
601 An alternative way to specify connection parameters is in a
602 <parameter>conninfo</parameter> string or
603 a <acronym>URI</acronym>, which is used instead of a database
604 name. This mechanism give you very wide control over the
605 connection. For example:
607 $ <userinput>psql "service=myservice sslmode=require"</userinput>
608 $ <userinput>psql postgresql://dbmaster:5433/mydb?sslmode=require</userinput>
610 This way you can also use LDAP for connection parameter lookup as
611 described in <xref linkend="libpq-ldap">.
612 See <xref linkend="libpq-connect"> for more information on all the
613 available connection options.
617 If the connection could not be made for any reason (e.g., insufficient
618 privileges, server is not running on the targeted host, etc.),
619 <application>psql</application> will return an error and terminate.
623 If at least one of standard input or standard output are a
624 terminal, then <application>psql</application> sets the client
625 encoding to <quote>auto</quote>, which will detect the
626 appropriate client encoding from the locale settings
627 (<envar>LC_CTYPE</envar> environment variable on Unix systems).
628 If this doesn't work out as expected, the client encoding can be
629 overridden using the environment
630 variable <envar>PGCLIENTENCODING</envar>.
634 <refsect2 id="R2-APP-PSQL-4">
635 <title>Entering SQL Commands</title>
638 In normal operation, <application>psql</application> provides a
639 prompt with the name of the database to which
640 <application>psql</application> is currently connected, followed by
641 the string <literal>=></literal>. For example:
643 $ <userinput>psql testdb</userinput>
645 Type "help" for help.
652 At the prompt, the user can type in <acronym>SQL</acronym> commands.
653 Ordinarily, input lines are sent to the server when a
654 command-terminating semicolon is reached. An end of line does not
655 terminate a command. Thus commands can be spread over several lines for
656 clarity. If the command was sent and executed without error, the results
657 of the command are displayed on the screen.
661 Whenever a command is executed, <application>psql</application> also polls
662 for asynchronous notification events generated by
663 <xref linkend="SQL-LISTEN"> and
664 <xref linkend="SQL-NOTIFY">.
668 <refsect2 id="APP-PSQL-meta-commands">
669 <title>Meta-Commands</title>
672 Anything you enter in <application>psql</application> that begins
673 with an unquoted backslash is a <application>psql</application>
674 meta-command that is processed by <application>psql</application>
675 itself. These commands make
676 <application>psql</application> more useful for administration or
677 scripting. Meta-commands are often called slash or backslash commands.
681 The format of a <application>psql</application> command is the backslash,
682 followed immediately by a command verb, then any arguments. The arguments
683 are separated from the command verb and each other by any number of
684 whitespace characters.
688 To include whitespace in an argument you can quote it with
689 single quotes. To include a single quote in an argument,
690 write two single quotes within single-quoted text.
691 Anything contained in single quotes is
692 furthermore subject to C-like substitutions for
693 <literal>\n</literal> (new line), <literal>\t</literal> (tab),
694 <literal>\b</literal> (backspace), <literal>\r</literal> (carriage return),
695 <literal>\f</literal> (form feed),
696 <literal>\</literal><replaceable>digits</replaceable> (octal), and
697 <literal>\x</literal><replaceable>digits</replaceable> (hexadecimal).
698 A backslash preceding any other character within single-quoted text
699 quotes that single character, whatever it is.
703 Within an argument, text that is enclosed in backquotes
704 (<literal>`</literal>) is taken as a command line that is passed to the
705 shell. The output of the command (with any trailing newline removed)
706 replaces the backquoted text.
710 If an unquoted colon (<literal>:</literal>) followed by a
711 <application>psql</> variable name appears within an argument, it is
712 replaced by the variable's value, as described in <xref
713 linkend="APP-PSQL-interpolation" endterm="APP-PSQL-interpolation-title">.
717 Some commands take an <acronym>SQL</acronym> identifier (such as a
718 table name) as argument. These arguments follow the syntax rules
719 of <acronym>SQL</acronym>: Unquoted letters are forced to
720 lowercase, while double quotes (<literal>"</>) protect letters
721 from case conversion and allow incorporation of whitespace into
722 the identifier. Within double quotes, paired double quotes reduce
723 to a single double quote in the resulting name. For example,
724 <literal>FOO"BAR"BAZ</> is interpreted as <literal>fooBARbaz</>,
725 and <literal>"A weird"" name"</> becomes <literal>A weird"
730 Parsing for arguments stops at the end of the line, or when another
731 unquoted backslash is found. An unquoted backslash
732 is taken as the beginning of a new meta-command. The special
733 sequence <literal>\\</literal> (two backslashes) marks the end of
734 arguments and continues parsing <acronym>SQL</acronym> commands, if
735 any. That way <acronym>SQL</acronym> and
736 <application>psql</application> commands can be freely mixed on a
737 line. But in any case, the arguments of a meta-command cannot
738 continue beyond the end of the line.
742 The following meta-commands are defined:
746 <term><literal>\a</literal></term>
749 If the current table output format is unaligned, it is switched to aligned.
750 If it is not unaligned, it is set to unaligned. This command is
751 kept for backwards compatibility. See <command>\pset</command> for a
752 more general solution.
758 <term><literal>\c</literal> or <literal>\connect</literal> <literal>[ <replaceable class="parameter">dbname</replaceable> [ <replaceable class="parameter">username</replaceable> ] [ <replaceable class="parameter">host</replaceable> ] [ <replaceable class="parameter">port</replaceable> ] ]</literal></term>
761 Establishes a new connection to a <productname>PostgreSQL</>
762 server. If the new connection is successfully made, the
763 previous connection is closed. If any of <replaceable
764 class="parameter">dbname</replaceable>, <replaceable
765 class="parameter">username</replaceable>, <replaceable
766 class="parameter">host</replaceable> or <replaceable
767 class="parameter">port</replaceable> are omitted or specified
768 as <literal>-</literal>, the value of that parameter from the
769 previous connection is used. If there is no previous
770 connection, the <application>libpq</application> default for
771 the parameter's value is used.
775 If the connection attempt failed (wrong user name, access
776 denied, etc.), the previous connection will only be kept if
777 <application>psql</application> is in interactive mode. When
778 executing a non-interactive script, processing will
779 immediately stop with an error. This distinction was chosen as
780 a user convenience against typos on the one hand, and a safety
781 mechanism that scripts are not accidentally acting on the
782 wrong database on the other hand.
788 <term><literal>\C [ <replaceable class="parameter">title</replaceable> ]</literal></term>
791 Sets the title of any tables being printed as the result of a
792 query or unset any such title. This command is equivalent to
793 <literal>\pset title <replaceable
794 class="parameter">title</replaceable></literal>. (The name of
795 this command derives from <quote>caption</quote>, as it was
796 previously only used to set the caption in an
797 <acronym>HTML</acronym> table.)
803 <term><literal>\cd [ <replaceable>directory</replaceable> ]</literal></term>
806 Changes the current working directory to
807 <replaceable>directory</replaceable>. Without argument, changes
808 to the current user's home directory.
813 To print your current working directory, use <literal>\! pwd</literal>.
820 <term><literal>\conninfo</literal></term>
823 Outputs information about the current database connection.
829 <term><literal>\copy { <replaceable class="parameter">table</replaceable> [ ( <replaceable class="parameter">column_list</replaceable> ) ] | ( <replaceable class="parameter">query</replaceable> ) }
830 { <literal>from</literal> | <literal>to</literal> }
831 { <replaceable class="parameter">filename</replaceable> | stdin | stdout | pstdin | pstdout }
835 [ delimiter [ as ] '<replaceable class="parameter">character</replaceable>' ]
836 [ null [ as ] '<replaceable class="parameter">string</replaceable>' ]
839 [ quote [ as ] '<replaceable class="parameter">character</replaceable>' ]
840 [ escape [ as ] '<replaceable class="parameter">character</replaceable>' ]
841 [ force quote <replaceable class="parameter">column_list</replaceable> | * ]
842 [ force not null <replaceable class="parameter">column_list</replaceable> ] ]</literal>
847 Performs a frontend (client) copy. This is an operation that
848 runs an <acronym>SQL</acronym> <xref linkend="SQL-COPY">
849 command, but instead of the server
850 reading or writing the specified file,
851 <application>psql</application> reads or writes the file and
852 routes the data between the server and the local file system.
853 This means that file accessibility and privileges are those of
854 the local user, not the server, and no SQL superuser
855 privileges are required.
859 The syntax of the command is similar to that of the
860 <acronym>SQL</acronym> <xref linkend="sql-copy">
861 command. Note that, because of this,
862 special parsing rules apply to the <command>\copy</command>
863 command. In particular, the variable substitution rules and
864 backslash escapes do not apply.
867 <para><literal>\copy ... from stdin | to stdout</literal>
868 reads/writes based on the command input and output respectively.
869 All rows are read from the same source that issued the command,
870 continuing until <literal>\.</literal> is read or the stream
871 reaches <acronym>EOF</>. Output is sent to the same place as
872 command output. To read/write from
873 <application>psql</application>'s standard input or output, use
874 <literal>pstdin</> or <literal>pstdout</>. This option is useful
875 for populating tables in-line within a SQL script file.
880 This operation is not as efficient as the <acronym>SQL</acronym>
881 <command>COPY</command> command because all data must pass
882 through the client/server connection. For large
883 amounts of data the <acronym>SQL</acronym> command might be preferable.
891 <term><literal>\copyright</literal></term>
894 Shows the copyright and distribution terms of
895 <productname>PostgreSQL</productname>.
901 <term><literal>\d[S+] [ <link linkend="APP-PSQL-patterns"><replaceable class="parameter">pattern</replaceable></link> ]</literal></term>
905 For each relation (table, view, index, sequence, or foreign table)
906 or composite type matching the
907 <replaceable class="parameter">pattern</replaceable>, show all
908 columns, their types, the tablespace (if not the default) and any
909 special attributes such as <literal>NOT NULL</literal> or defaults.
910 Associated indexes, constraints, rules, and triggers are
911 also shown. For foreign tables, the associated foreign
912 server is shown as well.
913 (<quote>Matching the pattern</> is defined in
914 <xref linkend="APP-PSQL-patterns" endterm="APP-PSQL-patterns-title">
919 For some types of relations, <literal>\d</> shows additional information
920 for each column: column values for sequences, indexed expression for
921 indexes and foreign data wrapper options for foreign tables.
925 The command form <literal>\d+</literal> is identical, except that
926 more information is displayed: any comments associated with the
927 columns of the table are shown, as is the presence of OIDs in the
928 table, the view definition if the relation is a view.
932 By default, only user-created objects are shown; supply a
933 pattern or the <literal>S</literal> modifier to include system
939 If <command>\d</command> is used without a
940 <replaceable class="parameter">pattern</replaceable> argument, it is
941 equivalent to <command>\dtvsE</command> which will show a list of
942 all visible tables, views, sequences and foreign tables.
943 This is purely a convenience measure.
950 <term><literal>\da[S] [ <link linkend="APP-PSQL-patterns"><replaceable class="parameter">pattern</replaceable></link> ]</literal></term>
954 Lists aggregate functions, together with their
955 return type and the data types they operate on. If <replaceable
956 class="parameter">pattern</replaceable>
957 is specified, only aggregates whose names match the pattern are shown.
958 By default, only user-created objects are shown; supply a
959 pattern or the <literal>S</literal> modifier to include system
967 <term><literal>\db[+] [ <link linkend="APP-PSQL-patterns"><replaceable class="parameter">pattern</replaceable></link> ]</literal></term>
971 Lists tablespaces. If <replaceable
972 class="parameter">pattern</replaceable>
973 is specified, only tablespaces whose names match the pattern are shown.
974 If <literal>+</literal> is appended to the command name, each object
975 is listed with its associated permissions.
982 <term><literal>\dc[S+] [ <link linkend="APP-PSQL-patterns"><replaceable class="parameter">pattern</replaceable></link> ]</literal></term>
985 Lists conversions between character-set encodings.
986 If <replaceable class="parameter">pattern</replaceable>
987 is specified, only conversions whose names match the pattern are
989 By default, only user-created objects are shown; supply a
990 pattern or the <literal>S</literal> modifier to include system
992 If <literal>+</literal> is appended to the command name, each object
993 is listed with its associated description.
1000 <term><literal>\dC[+] [ <link linkend="APP-PSQL-patterns"><replaceable class="parameter">pattern</replaceable></link> ]</literal></term>
1004 If <replaceable class="parameter">pattern</replaceable>
1005 is specified, only casts whose source or target types match the
1007 If <literal>+</literal> is appended to the command name, each object
1008 is listed with its associated description.
1015 <term><literal>\dd[S] [ <link linkend="APP-PSQL-patterns"><replaceable class="parameter">pattern</replaceable></link> ]</literal></term>
1018 Shows the descriptions of objects of type <literal>constraint</>,
1019 <literal>operator class</>, <literal>operator family</>,
1020 <literal>rule</>, and <literal>trigger</>. All
1021 other comments may be viewed by the respective backslash commands for
1025 <para><literal>\dd</literal> displays descriptions for objects matching the
1026 <replaceable class="parameter">pattern</replaceable>, or of visible
1027 objects of the appropriate type if no argument is given. But in either
1028 case, only objects that have a description are listed.
1029 By default, only user-created objects are shown; supply a
1030 pattern or the <literal>S</literal> modifier to include system
1035 Descriptions for objects can be created with the <xref
1036 linkend="sql-comment">
1037 <acronym>SQL</acronym> command.
1044 <term><literal>\ddp [ <link linkend="APP-PSQL-patterns"><replaceable class="parameter">pattern</replaceable></link> ]</literal></term>
1047 Lists default access privilege settings. An entry is shown for
1048 each role (and schema, if applicable) for which the default
1049 privilege settings have been changed from the built-in defaults.
1050 If <replaceable class="parameter">pattern</replaceable> is
1051 specified, only entries whose role name or schema name matches
1052 the pattern are listed.
1056 The <xref linkend="sql-alterdefaultprivileges"> command is used to set
1057 default access privileges. The meaning of the
1058 privilege display is explained under
1059 <xref linkend="sql-grant">.
1066 <term><literal>\dD[S+] [ <link linkend="APP-PSQL-patterns"><replaceable class="parameter">pattern</replaceable></link> ]</literal></term>
1069 Lists domains. If <replaceable
1070 class="parameter">pattern</replaceable>
1071 is specified, only domains whose names match the pattern are shown.
1072 By default, only user-created objects are shown; supply a
1073 pattern or the <literal>S</literal> modifier to include system
1075 If <literal>+</literal> is appended to the command name, each object
1076 is listed with its associated permissions and description.
1083 <term><literal>\dE[S+] [ <link linkend="APP-PSQL-patterns"><replaceable class="parameter">pattern</replaceable></link> ]</literal></term>
1084 <term><literal>\di[S+] [ <link linkend="APP-PSQL-patterns"><replaceable class="parameter">pattern</replaceable></link> ]</literal></term>
1085 <term><literal>\ds[S+] [ <link linkend="APP-PSQL-patterns"><replaceable class="parameter">pattern</replaceable></link> ]</literal></term>
1086 <term><literal>\dt[S+] [ <link linkend="APP-PSQL-patterns"><replaceable class="parameter">pattern</replaceable></link> ]</literal></term>
1087 <term><literal>\dv[S+] [ <link linkend="APP-PSQL-patterns"><replaceable class="parameter">pattern</replaceable></link> ]</literal></term>
1091 In this group of commands, the letters <literal>E</literal>,
1092 <literal>i</literal>, <literal>s</literal>,
1093 <literal>t</literal>, and <literal>v</literal>
1094 stand for foreign table, index, sequence, table, and view,
1096 You can specify any or all of
1097 these letters, in any order, to obtain a listing of objects
1098 of these types. For example, <literal>\dit</> lists indexes
1099 and tables. If <literal>+</literal> is
1100 appended to the command name, each object is listed with its
1101 physical size on disk and its associated description, if any.
1102 If <replaceable class="parameter">pattern</replaceable> is
1103 specified, only objects whose names match the pattern are listed.
1104 By default, only user-created objects are shown; supply a
1105 pattern or the <literal>S</literal> modifier to include system
1113 <term><literal>\des[+] [ <link linkend="APP-PSQL-patterns"><replaceable class="parameter">pattern</replaceable></link> ]</literal></term>
1116 Lists foreign servers (mnemonic: <quote>external
1118 If <replaceable class="parameter">pattern</replaceable> is
1119 specified, only those servers whose name matches the pattern
1120 are listed. If the form <literal>\des+</literal> is used, a
1121 full description of each server is shown, including the
1122 server's ACL, type, version, options, and description.
1129 <term><literal>\det[+] [ <link linkend="APP-PSQL-patterns"><replaceable class="parameter">pattern</replaceable></link> ]</literal></term>
1132 Lists foreign tables (mnemonic: <quote>external tables</quote>).
1133 If <replaceable class="parameter">pattern</replaceable> is
1134 specified, only entries whose table name or schema name matches
1135 the pattern are listed. If the form <literal>\det+</literal>
1136 is used, generic options and the foreign table description
1144 <term><literal>\deu[+] [ <link linkend="APP-PSQL-patterns"><replaceable class="parameter">pattern</replaceable></link> ]</literal></term>
1147 Lists user mappings (mnemonic: <quote>external
1149 If <replaceable class="parameter">pattern</replaceable> is
1150 specified, only those mappings whose user names match the
1151 pattern are listed. If the form <literal>\deu+</literal> is
1152 used, additional information about each mapping is shown.
1157 <literal>\deu+</literal> might also display the user name and
1158 password of the remote user, so care should be taken not to
1167 <term><literal>\dew[+] [ <link linkend="APP-PSQL-patterns"><replaceable class="parameter">pattern</replaceable></link> ]</literal></term>
1170 Lists foreign-data wrappers (mnemonic: <quote>external
1172 If <replaceable class="parameter">pattern</replaceable> is
1173 specified, only those foreign-data wrappers whose name matches
1174 the pattern are listed. If the form <literal>\dew+</literal>
1175 is used, the ACL, options, and description of the foreign-data
1176 wrapper are also shown.
1183 <term><literal>\df[antwS+] [ <link linkend="APP-PSQL-patterns"><replaceable class="parameter">pattern</replaceable></link> ]</literal></term>
1187 Lists functions, together with their arguments, return types, and
1188 function types, which are classified as <quote>agg</> (aggregate),
1189 <quote>normal</>, <quote>trigger</>, or <quote>window</>.
1190 To display only functions
1191 of specific type(s), add the corresponding letters <literal>a</>,
1192 <literal>n</>, <literal>t</>, or <literal>w</> to the command.
1194 class="parameter">pattern</replaceable> is specified, only
1195 functions whose names match the pattern are shown. If the
1196 form <literal>\df+</literal> is used, additional information
1197 about each function, including volatility, language, source
1198 code and description, is shown. By default, only user-created
1199 objects are shown; supply a pattern or the <literal>S</literal>
1200 modifier to include system objects.
1205 To look up functions taking arguments or returning values of a specific
1206 type, use your pager's search capability to scroll through the
1207 <literal>\df</> output.
1215 <term><literal>\dF[+] [ <link linkend="APP-PSQL-patterns"><replaceable class="parameter">pattern</replaceable></link> ]</literal></term>
1218 Lists text search configurations.
1219 If <replaceable class="parameter">pattern</replaceable> is specified,
1220 only configurations whose names match the pattern are shown.
1221 If the form <literal>\dF+</literal> is used, a full description of
1222 each configuration is shown, including the underlying text search
1223 parser and the dictionary list for each parser token type.
1229 <term><literal>\dFd[+] [ <link linkend="APP-PSQL-patterns"><replaceable class="parameter">pattern</replaceable></link> ]</literal></term>
1232 Lists text search dictionaries.
1233 If <replaceable class="parameter">pattern</replaceable> is specified,
1234 only dictionaries whose names match the pattern are shown.
1235 If the form <literal>\dFd+</literal> is used, additional information
1236 is shown about each selected dictionary, including the underlying
1237 text search template and the option values.
1243 <term><literal>\dFp[+] [ <link linkend="APP-PSQL-patterns"><replaceable class="parameter">pattern</replaceable></link> ]</literal></term>
1246 Lists text search parsers.
1247 If <replaceable class="parameter">pattern</replaceable> is specified,
1248 only parsers whose names match the pattern are shown.
1249 If the form <literal>\dFp+</literal> is used, a full description of
1250 each parser is shown, including the underlying functions and the
1251 list of recognized token types.
1257 <term><literal>\dFt[+] [ <link linkend="APP-PSQL-patterns"><replaceable class="parameter">pattern</replaceable></link> ]</literal></term>
1260 Lists text search templates.
1261 If <replaceable class="parameter">pattern</replaceable> is specified,
1262 only templates whose names match the pattern are shown.
1263 If the form <literal>\dFt+</literal> is used, additional information
1264 is shown about each template, including the underlying function names.
1271 <term><literal>\dg[+] [ <link linkend="APP-PSQL-patterns"><replaceable class="parameter">pattern</replaceable></link> ]</literal></term>
1274 Lists database roles.
1275 (Since the concepts of <quote>users</> and <quote>groups</> have been
1276 unified into <quote>roles</>, this command is now equivalent to
1277 <literal>\du</literal>.)
1278 If <replaceable class="parameter">pattern</replaceable> is specified,
1279 only those roles whose names match the pattern are listed.
1280 If the form <literal>\dg+</literal> is used, additional information
1281 is shown about each role; currently this adds the comment for each
1289 <term><literal>\dl</literal></term>
1292 This is an alias for <command>\lo_list</command>, which shows a
1293 list of large objects.
1299 <term><literal>\dL[S+] [ <link linkend="APP-PSQL-patterns"><replaceable class="parameter">pattern</replaceable></link> ]</literal></term>
1302 Lists procedural languages. If <replaceable
1303 class="parameter">pattern</replaceable>
1304 is specified, only languages whose names match the pattern are listed.
1305 By default, only user-created languages
1306 are shown; supply the <literal>S</literal> modifier to include system
1307 objects. If <literal>+</literal> is appended to the command name, each
1308 language is listed with its call handler, validator, access privileges,
1309 and whether it is a system object.
1316 <term><literal>\dn[S+] [ <link linkend="APP-PSQL-patterns"><replaceable class="parameter">pattern</replaceable></link> ]</literal></term>
1320 Lists schemas (namespaces). If <replaceable
1321 class="parameter">pattern</replaceable>
1322 is specified, only schemas whose names match the pattern are listed.
1323 By default, only user-created objects are shown; supply a
1324 pattern or the <literal>S</literal> modifier to include system objects.
1325 If <literal>+</literal> is appended to the command name, each object
1326 is listed with its associated permissions and description, if any.
1333 <term><literal>\do[S] [ <link linkend="APP-PSQL-patterns"><replaceable class="parameter">pattern</replaceable></link> ]</literal></term>
1336 Lists operators with their operand and return types.
1337 If <replaceable class="parameter">pattern</replaceable> is
1338 specified, only operators whose names match the pattern are listed.
1339 By default, only user-created objects are shown; supply a
1340 pattern or the <literal>S</literal> modifier to include system
1348 <term><literal>\dO[S+] [ <link linkend="APP-PSQL-patterns"><replaceable class="parameter">pattern</replaceable></link> ]</literal></term>
1352 If <replaceable class="parameter">pattern</replaceable> is
1353 specified, only collations whose names match the pattern are
1354 listed. By default, only user-created objects are shown;
1355 supply a pattern or the <literal>S</literal> modifier to
1356 include system objects. If <literal>+</literal> is appended
1357 to the command name, each collation is listed with its associated
1358 description, if any.
1359 Note that only collations usable with the current database's encoding
1360 are shown, so the results may vary in different databases of the
1368 <term><literal>\dp [ <link linkend="APP-PSQL-patterns"><replaceable class="parameter">pattern</replaceable></link> ]</literal></term>
1371 Lists tables, views and sequences with their
1372 associated access privileges.
1373 If <replaceable class="parameter">pattern</replaceable> is
1374 specified, only tables, views and sequences whose names match the
1379 The <xref linkend="sql-grant"> and
1380 <xref linkend="sql-revoke">
1381 commands are used to set access privileges. The meaning of the
1382 privilege display is explained under
1383 <xref linkend="sql-grant">.
1389 <term><literal>\drds [ <link linkend="APP-PSQL-patterns"><replaceable class="parameter">role-pattern</replaceable></link> [ <link linkend="APP-PSQL-patterns"><replaceable class="parameter">database-pattern</replaceable></link> ] ]</literal></term>
1392 Lists defined configuration settings. These settings can be
1393 role-specific, database-specific, or both.
1394 <replaceable>role-pattern</replaceable> and
1395 <replaceable>database-pattern</replaceable> are used to select
1396 specific roles and databases to list, respectively. If omitted, or if
1397 <literal>*</> is specified, all settings are listed, including those
1398 not role-specific or database-specific, respectively.
1402 The <xref linkend="sql-alterrole"> and
1403 <xref linkend="sql-alterdatabase">
1404 commands are used to define per-role and per-database configuration
1411 <term><literal>\dT[S+] [ <link linkend="APP-PSQL-patterns"><replaceable class="parameter">pattern</replaceable></link> ]</literal></term>
1415 If <replaceable class="parameter">pattern</replaceable> is
1416 specified, only types whose names match the pattern are listed.
1417 If <literal>+</literal> is appended to the command name, each type is
1418 listed with its internal name and size, its allowed values
1419 if it is an <type>enum</> type, and its associated permissions.
1420 By default, only user-created objects are shown; supply a
1421 pattern or the <literal>S</literal> modifier to include system
1428 <term><literal>\du[+] [ <link linkend="APP-PSQL-patterns"><replaceable class="parameter">pattern</replaceable></link> ]</literal></term>
1431 Lists database roles.
1432 (Since the concepts of <quote>users</> and <quote>groups</> have been
1433 unified into <quote>roles</>, this command is now equivalent to
1434 <literal>\dg</literal>.)
1435 If <replaceable class="parameter">pattern</replaceable> is specified,
1436 only those roles whose names match the pattern are listed.
1437 If the form <literal>\du+</literal> is used, additional information
1438 is shown about each role; currently this adds the comment for each
1445 <term><literal>\dx[+] [ <link linkend="APP-PSQL-patterns"><replaceable class="parameter">pattern</replaceable></link> ]</literal></term>
1448 Lists installed extensions.
1449 If <replaceable class="parameter">pattern</replaceable>
1450 is specified, only those extensions whose names match the pattern
1452 If the form <literal>\dx+</literal> is used, all the objects belonging
1453 to each matching extension are listed.
1459 <term><literal>\e</literal> or <literal>\edit</> <literal> <optional> <replaceable class="parameter">filename</> </optional> <optional> <replaceable class="parameter">line_number</> </optional> </literal></term>
1463 If <replaceable class="parameter">filename</replaceable> is
1464 specified, the file is edited; after the editor exits, its
1465 content is copied back to the query buffer. If no <replaceable
1466 class="parameter">filename</replaceable> is given, the current query
1467 buffer is copied to a temporary file which is then edited in the same
1472 The new query buffer is then re-parsed according to the normal
1473 rules of <application>psql</application>, where the whole buffer
1474 is treated as a single line. (Thus you cannot make scripts this
1475 way. Use <command>\i</command> for that.) This means that
1476 if the query ends with (or contains) a semicolon, it is
1477 immediately executed. Otherwise it will merely wait in the
1478 query buffer; type semicolon or <literal>\g</> to send it, or
1479 <literal>\r</> to cancel.
1483 If a line number is specified, <application>psql</application> will
1484 position the cursor on the specified line of the file or query buffer.
1485 Note that if a single all-digits argument is given,
1486 <application>psql</application> assumes it is a line number,
1492 See under <xref linkend="app-psql-environment"
1493 endterm="app-psql-environment-title"> for how to configure and
1494 customize your editor.
1501 <term><literal>\echo <replaceable class="parameter">text</replaceable> [ ... ]</literal></term>
1504 Prints the arguments to the standard output, separated by one
1505 space and followed by a newline. This can be useful to
1506 intersperse information in the output of scripts. For example:
1508 => <userinput>\echo `date`</userinput>
1509 Tue Oct 26 21:40:57 CEST 1999
1511 If the first argument is an unquoted <literal>-n</literal> the trailing
1512 newline is not written.
1517 If you use the <command>\o</command> command to redirect your
1518 query output you might wish to use <command>\qecho</command>
1519 instead of this command.
1526 <term><literal>\ef <optional> <replaceable class="parameter">function_description</> <optional> <replaceable class="parameter">line_number</> </optional> </optional> </literal></term>
1530 This command fetches and edits the definition of the named function,
1531 in the form of a <command>CREATE OR REPLACE FUNCTION</> command.
1532 Editing is done in the same way as for <literal>\edit</>.
1533 After the editor exits, the updated command waits in the query buffer;
1534 type semicolon or <literal>\g</> to send it, or <literal>\r</>
1539 The target function can be specified by name alone, or by name
1540 and arguments, for example <literal>foo(integer, text)</>.
1541 The argument types must be given if there is more
1542 than one function of the same name.
1546 If no function is specified, a blank <command>CREATE FUNCTION</>
1547 template is presented for editing.
1551 If a line number is specified, <application>psql</application> will
1552 position the cursor on the specified line of the function body.
1553 (Note that the function body typically does not begin on the first
1559 See under <xref linkend="app-psql-environment"
1560 endterm="app-psql-environment-title"> for how to configure and
1561 customize your editor.
1569 <term><literal>\encoding [ <replaceable class="parameter">encoding</replaceable> ]</literal></term>
1573 Sets the client character set encoding. Without an argument, this command
1574 shows the current encoding.
1581 <term><literal>\f [ <replaceable class="parameter">string</replaceable> ]</literal></term>
1585 Sets the field separator for unaligned query output. The default
1586 is the vertical bar (<literal>|</literal>). See also
1587 <command>\pset</command> for a generic way of setting output
1595 <term><literal>\g</literal> [ { <replaceable class="parameter">filename</replaceable> | <literal>|</literal><replaceable class="parameter">command</replaceable> } ]</term>
1599 Sends the current query input buffer to the server and
1600 optionally stores the query's output in <replaceable
1601 class="parameter">filename</replaceable> or pipes the output
1602 into a separate Unix shell executing <replaceable
1603 class="parameter">command</replaceable>. A bare
1604 <literal>\g</literal> is virtually equivalent to a semicolon. A
1605 <literal>\g</literal> with argument is a <quote>one-shot</quote>
1606 alternative to the <command>\o</command> command.
1612 <term><literal>\h</literal> or <literal>\help</literal> <literal>[ <replaceable class="parameter">command</replaceable> ]</literal></term>
1615 Gives syntax help on the specified <acronym>SQL</acronym>
1616 command. If <replaceable class="parameter">command</replaceable>
1617 is not specified, then <application>psql</application> will list
1618 all the commands for which syntax help is available. If
1619 <replaceable class="parameter">command</replaceable> is an
1620 asterisk (<literal>*</literal>), then syntax help on all
1621 <acronym>SQL</acronym> commands is shown.
1626 To simplify typing, commands that consists of several words do
1627 not have to be quoted. Thus it is fine to type <userinput>\help
1628 alter table</userinput>.
1636 <term><literal>\H</literal></term>
1639 Turns on <acronym>HTML</acronym> query output format. If the
1640 <acronym>HTML</acronym> format is already on, it is switched
1641 back to the default aligned text format. This command is for
1642 compatibility and convenience, but see <command>\pset</command>
1643 about setting other output options.
1650 <term><literal>\i <replaceable class="parameter">filename</replaceable></literal></term>
1653 Reads input from the file <replaceable
1654 class="parameter">filename</replaceable> and executes it as
1655 though it had been typed on the keyboard.
1659 If you want to see the lines on the screen as they are read you
1660 must set the variable <varname>ECHO</varname> to
1661 <literal>all</literal>.
1669 <term><literal>\ir <replaceable class="parameter">filename</replaceable></literal></term>
1672 The <literal>\ir</> command is similar to <literal>\i</>, but resolves
1673 relative pathnames differently. When executing in interactive mode,
1674 the two commands behave identically. However, when invoked from a
1675 script, <literal>\ir</literal> interprets pathnames relative to the
1676 directory in which the script is located, rather than the current
1684 <term><literal>\l</literal> (or <literal>\list</literal>)</term>
1685 <term><literal>\l+</literal> (or <literal>\list+</literal>)</term>
1688 List the names, owners, character set encodings, and access privileges
1689 of all the databases in the server.
1690 If <literal>+</literal> is appended to the command name, database
1691 sizes, default tablespaces, and descriptions are also displayed.
1692 (Size information is only available for databases that the current
1693 user can connect to.)
1700 <term><literal>\lo_export <replaceable class="parameter">loid</replaceable> <replaceable class="parameter">filename</replaceable></literal></term>
1704 Reads the large object with <acronym>OID</acronym> <replaceable
1705 class="parameter">loid</replaceable> from the database and
1706 writes it to <replaceable
1707 class="parameter">filename</replaceable>. Note that this is
1708 subtly different from the server function
1709 <function>lo_export</function>, which acts with the permissions
1710 of the user that the database server runs as and on the server's
1715 Use <command>\lo_list</command> to find out the large object's
1716 <acronym>OID</acronym>.
1724 <term><literal>\lo_import <replaceable class="parameter">filename</replaceable> [ <replaceable class="parameter">comment</replaceable> ]</literal></term>
1728 Stores the file into a <productname>PostgreSQL</productname>
1729 large object. Optionally, it associates the given
1730 comment with the object. Example:
1732 foo=> <userinput>\lo_import '/home/peter/pictures/photo.xcf' 'a picture of me'</userinput>
1735 The response indicates that the large object received object
1736 ID 152801, which can be used to access the newly-created large
1737 object in the future. For the sake of readability, it is
1738 recommended to always associate a human-readable comment with
1739 every object. Both OIDs and comments can be viewed with the
1740 <command>\lo_list</command> command.
1744 Note that this command is subtly different from the server-side
1745 <function>lo_import</function> because it acts as the local user
1746 on the local file system, rather than the server's user and file
1753 <term><literal>\lo_list</literal></term>
1756 Shows a list of all <productname>PostgreSQL</productname>
1757 large objects currently stored in the database,
1758 along with any comments provided for them.
1764 <term><literal>\lo_unlink <replaceable class="parameter">loid</replaceable></literal></term>
1768 Deletes the large object with <acronym>OID</acronym>
1769 <replaceable class="parameter">loid</replaceable> from the
1775 Use <command>\lo_list</command> to find out the large object's
1776 <acronym>OID</acronym>.
1784 <term><literal>\o</literal> [ {<replaceable class="parameter">filename</replaceable> | <literal>|</literal><replaceable class="parameter">command</replaceable>} ]</term>
1788 Saves future query results to the file <replaceable
1789 class="parameter">filename</replaceable> or pipes future results
1790 into a separate Unix shell to execute <replaceable
1791 class="parameter">command</replaceable>. If no arguments are
1792 specified, the query output will be reset to the standard output.
1795 <para><quote>Query results</quote> includes all tables, command
1796 responses, and notices obtained from the database server, as
1797 well as output of various backslash commands that query the
1798 database (such as <command>\d</command>), but not error
1804 To intersperse text output in between query results, use
1805 <command>\qecho</command>.
1813 <term><literal>\p</literal></term>
1816 Print the current query buffer to the standard output.
1822 <term><literal>\password [ <replaceable class="parameter">username</replaceable> ]</literal></term>
1825 Changes the password of the specified user (by default, the current
1826 user). This command prompts for the new password, encrypts it, and
1827 sends it to the server as an <command>ALTER ROLE</> command. This
1828 makes sure that the new password does not appear in cleartext in the
1829 command history, the server log, or elsewhere.
1835 <term><literal>\prompt [ <replaceable class="parameter">text</replaceable> ] <replaceable class="parameter">name</replaceable></literal></term>
1838 Prompts the user to supply text, which is assigned to the variable
1839 <replaceable class="parameter">name</>.
1840 An optional prompt string, <replaceable
1841 class="parameter">text</>, can be specified. (For multiword
1842 prompts, surround the text with single quotes.)
1846 By default, <literal>\prompt</> uses the terminal for input and
1847 output. However, if the <option>-f</> command line switch was
1848 used, <literal>\prompt</> uses standard input and standard output.
1854 <term><literal>\pset <replaceable class="parameter">option</replaceable> [ <replaceable class="parameter">value</replaceable> ]</literal></term>
1858 This command sets options affecting the output of query result tables.
1859 <replaceable class="parameter">option</replaceable>
1860 indicates which option is to be set. The semantics of
1861 <replaceable class="parameter">value</replaceable> vary depending
1862 on the selected option. For some options, omitting <replaceable
1863 class="parameter">value</replaceable> causes the option to be toggled
1864 or unset, as described under the particular option. If no such
1865 behavior is mentioned, then omitting
1866 <replaceable class="parameter">value</replaceable> just results in
1867 the current setting being displayed.
1871 Adjustable printing options are:
1874 <term><literal>border</literal></term>
1877 The <replaceable class="parameter">value</replaceable> must be a
1878 number. In general, the higher
1879 the number the more borders and lines the tables will have,
1880 but this depends on the particular format. In
1881 <acronym>HTML</acronym> format, this will translate directly
1882 into the <literal>border=...</literal> attribute; in the
1883 other formats only values 0 (no border), 1 (internal dividing lines),
1884 and 2 (table frame) make sense.
1890 <term><literal>columns</literal></term>
1893 Sets the target width for the <literal>wrapped</> format, and also
1894 the width limit for determining whether output is wide enough to
1895 require the pager or switch to the vertical display in expanded auto
1897 Zero (the default) causes the target width to be controlled by the
1898 environment variable <envar>COLUMNS</>, or the detected screen width
1899 if <envar>COLUMNS</> is not set.
1900 In addition, if <literal>columns</> is zero then the
1901 <literal>wrapped</> format only affects screen output.
1902 If <literal>columns</> is nonzero then file and pipe output is
1903 wrapped to that width as well.
1909 <term><literal>expanded</literal> (or <literal>x</literal>)</term>
1912 If <replaceable class="parameter">value</replaceable> is specified it
1913 must be either <literal>on</literal> or <literal>off</literal>, which
1914 will enable or disable expanded mode, or <literal>auto</literal>.
1915 If <replaceable class="parameter">value</replaceable> is omitted the
1916 command toggles between the on and off settings. When expanded mode
1917 is enabled, query results are displayed in two columns, with the
1918 column name on the left and the data on the right. This mode is
1919 useful if the data wouldn't fit on the screen in the
1920 normal <quote>horizontal</quote> mode. In the auto setting, the
1921 expanded mode is used whenever the query output is wider than the
1922 screen, otherwise the regular mode is used. The auto setting is only
1923 effective in the aligned and wrapped formats. In other formats, it
1924 always behaves as if the expanded mode is off.
1930 <term><literal>fieldsep</literal></term>
1933 Specifies the field separator to be used in unaligned output
1934 format. That way one can create, for example, tab- or
1935 comma-separated output, which other programs might prefer. To
1936 set a tab as field separator, type <literal>\pset fieldsep
1937 '\t'</literal>. The default field separator is
1938 <literal>'|'</literal> (a vertical bar).
1944 <term><literal>fieldsep_zero</literal></term>
1947 Sets the field separator to use in unaligned output format to a zero
1954 <term><literal>footer</literal></term>
1957 If <replaceable class="parameter">value</replaceable> is specified
1958 it must be either <literal>on</literal> or <literal>off</literal>
1959 which will enable or disable display of the table footer
1960 (the <literal>(<replaceable>n</> rows)</literal> count).
1961 If <replaceable class="parameter">value</replaceable> is omitted the
1962 command toggles footer display on or off.
1968 <term><literal>format</literal></term>
1971 Sets the output format to one of <literal>unaligned</literal>,
1972 <literal>aligned</literal>, <literal>wrapped</literal>,
1973 <literal>html</literal>,
1974 <literal>latex</literal>, or <literal>troff-ms</literal>.
1975 Unique abbreviations are allowed. (That would mean one letter
1979 <para><literal>unaligned</> format writes all columns of a row on one
1980 line, separated by the currently active field separator. This
1981 is useful for creating output that might be intended to be read
1982 in by other programs (for example, tab-separated or comma-separated
1986 <para><literal>aligned</literal> format is the standard, human-readable,
1987 nicely formatted text output; this is the default.
1990 <para><literal>wrapped</> format is like <literal>aligned</> but wraps
1991 wide data values across lines to make the output fit in the target
1992 column width. The target width is determined as described under
1993 the <literal>columns</> option. Note that <application>psql</> will
1994 not attempt to wrap column header titles; therefore,
1995 <literal>wrapped</> format behaves the same as <literal>aligned</>
1996 if the total width needed for column headers exceeds the target.
2000 The <literal>html</>, <literal>latex</>, and <literal>troff-ms</>
2001 formats put out tables that are intended to
2002 be included in documents using the respective mark-up
2003 language. They are not complete documents! (This might not be
2004 so dramatic in <acronym>HTML</acronym>, but in LaTeX you must
2005 have a complete document wrapper.)
2011 <term><literal>linestyle</literal></term>
2014 Sets the border line drawing style to one
2015 of <literal>ascii</literal>, <literal>old-ascii</literal>
2016 or <literal>unicode</literal>.
2017 Unique abbreviations are allowed. (That would mean one
2019 The default setting is <literal>ascii</>.
2020 This option only affects the <literal>aligned</> and
2021 <literal>wrapped</> output formats.
2024 <para><literal>ascii</literal> style uses plain <acronym>ASCII</acronym>
2025 characters. Newlines in data are shown using
2026 a <literal>+</literal> symbol in the right-hand margin.
2027 When the <literal>wrapped</literal> format wraps data from
2028 one line to the next without a newline character, a dot
2029 (<literal>.</>) is shown in the right-hand margin of the first line,
2030 and again in the left-hand margin of the following line.
2033 <para><literal>old-ascii</literal> style uses plain <acronym>ASCII</>
2034 characters, using the formatting style used
2035 in <productname>PostgreSQL</productname> 8.4 and earlier.
2036 Newlines in data are shown using a <literal>:</literal>
2037 symbol in place of the left-hand column separator.
2038 When the data is wrapped from one line
2039 to the next without a newline character, a <literal>;</>
2040 symbol is used in place of the left-hand column separator.
2043 <para><literal>unicode</literal> style uses Unicode box-drawing characters.
2044 Newlines in data are shown using a carriage return symbol
2045 in the right-hand margin. When the data is wrapped from one line
2046 to the next without a newline character, an ellipsis symbol
2047 is shown in the right-hand margin of the first line, and
2048 again in the left-hand margin of the following line.
2052 When the <literal>border</> setting is greater than zero,
2053 this option also determines the characters
2054 with which the border lines are drawn.
2055 Plain <acronym>ASCII</acronym> characters work everywhere, but
2056 Unicode characters look nicer on displays that recognize them.
2062 <term><literal>null</literal></term>
2065 Sets the string to be printed in place of a null value.
2066 The default is to print nothing, which can easily be mistaken for
2067 an empty string. For example, one might prefer <literal>\pset null
2074 <term><literal>numericlocale</literal></term>
2077 If <replaceable class="parameter">value</replaceable> is specified
2078 it must be either <literal>on</literal> or <literal>off</literal>
2079 which will enable or disable display of a locale-specific character
2080 to separate groups of digits to the left of the decimal marker.
2081 If <replaceable class="parameter">value</replaceable> is omitted the
2082 command toggles between regular and locale-specific numeric output.
2088 <term><literal>pager</literal></term>
2091 Controls use of a pager program for query and <application>psql</>
2092 help output. If the environment variable <envar>PAGER</envar>
2093 is set, the output is piped to the specified program.
2094 Otherwise a platform-dependent default (such as
2095 <filename>more</filename>) is used.
2099 When the <literal>pager</> option is <literal>off</>, the pager
2100 program is not used. When the <literal>pager</> option is
2101 <literal>on</>, the pager is used when appropriate, i.e., when the
2102 output is to a terminal and will not fit on the screen.
2103 The <literal>pager</> option can also be set to <literal>always</>,
2104 which causes the pager to be used for all terminal output regardless
2105 of whether it fits on the screen. <literal>\pset pager</>
2106 without a <replaceable class="parameter">value</replaceable>
2107 toggles pager use on and off.
2113 <term><literal>recordsep</literal></term>
2116 Specifies the record (line) separator to use in unaligned
2117 output format. The default is a newline character.
2123 <term><literal>recordsep_zero</literal></term>
2126 Sets the record separator to use in unaligned output format to a zero
2133 <term><literal>tableattr</literal> (or <literal>T</literal>)</term>
2136 Specifies attributes to be placed inside the
2137 <acronym>HTML</acronym> <sgmltag>table</sgmltag> tag in
2138 <literal>html</> output format. This
2139 could for example be <literal>cellpadding</literal> or
2140 <literal>bgcolor</literal>. Note that you probably don't want
2141 to specify <literal>border</literal> here, as that is already
2142 taken care of by <literal>\pset border</literal>.
2144 <replaceable class="parameter">value</replaceable> is given,
2145 the table attributes are unset.
2151 <term><literal>title</literal></term>
2154 Sets the table title for any subsequently printed tables. This
2155 can be used to give your output descriptive tags. If no
2156 <replaceable class="parameter">value</replaceable> is given,
2163 <term><literal>tuples_only</literal> (or <literal>t</literal>)</term>
2166 If <replaceable class="parameter">value</replaceable> is specified
2167 it must be either <literal>on</literal> or <literal>off</literal>
2168 which will enable or disable tuples-only mode.
2169 If <replaceable class="parameter">value</replaceable> is omitted the
2170 command toggles between regular and tuples-only output.
2171 Regular output includes extra information such
2172 as column headers, titles, and various footers. In tuples-only
2173 mode, only actual table data is shown.
2181 Illustrations of how these different formats look can be seen in
2182 the <xref linkend="APP-PSQL-examples"
2183 endterm="APP-PSQL-examples-title"> section.
2188 There are various shortcut commands for <command>\pset</command>. See
2189 <command>\a</command>, <command>\C</command>, <command>\H</command>,
2190 <command>\t</command>, <command>\T</command>, and <command>\x</command>.
2196 It is an error to call <command>\pset</command> without any
2197 arguments. In the future this case might show the current status
2198 of all printing options.
2207 <term><literal>\q</literal> or <literal>\quit</literal></term>
2210 Quits the <application>psql</application> program.
2211 In a script file, only execution of that script is terminated.
2218 <term><literal>\qecho <replaceable class="parameter">text</replaceable> [ ... ] </literal></term>
2221 This command is identical to <command>\echo</command> except
2222 that the output will be written to the query output channel, as
2223 set by <command>\o</command>.
2230 <term><literal>\r</literal></term>
2233 Resets (clears) the query buffer.
2240 <term><literal>\s [ <replaceable class="parameter">filename</replaceable> ]</literal></term>
2243 Print or save the command line history to <replaceable
2244 class="parameter">filename</replaceable>. If <replaceable
2245 class="parameter">filename</replaceable> is omitted, the history
2246 is written to the standard output. This option is only available
2247 if <application>psql</application> is configured to use the
2248 <acronym>GNU</acronym> <application>Readline</application> library.
2255 <term><literal>\set [ <replaceable class="parameter">name</replaceable> [ <replaceable class="parameter">value</replaceable> [ ... ] ] ]</literal></term>
2259 Sets the <application>psql</> variable <replaceable
2260 class="parameter">name</replaceable> to <replaceable
2261 class="parameter">value</replaceable>, or if more than one value
2262 is given, to the concatenation of all of them. If only one
2263 argument is given, the variable is set with an empty value. To
2264 unset a variable, use the <command>\unset</command> command.
2268 <command>\set</> without any arguments displays the names and values
2269 of all currently-set <application>psql</> variables.
2273 Valid variable names can contain letters, digits, and
2274 underscores. See the section <xref
2275 linkend="APP-PSQL-variables"
2276 endterm="APP-PSQL-variables-title"> below for details.
2277 Variable names are case-sensitive.
2281 Although you are welcome to set any variable to anything you
2282 want, <application>psql</application> treats several variables
2283 as special. They are documented in the section about variables.
2288 This command is unrelated to the <acronym>SQL</acronym>
2289 command <xref linkend="SQL-SET">.
2297 <term><literal>\setenv [ <replaceable class="parameter">name</replaceable> [ <replaceable class="parameter">value</replaceable> ] ]</literal></term>
2301 Sets the environment variable <replaceable
2302 class="parameter">name</replaceable> to <replaceable
2303 class="parameter">value</replaceable>, or if the
2304 <replaceable class="parameter">value</replaceable> is
2305 not supplied, unsets the environment variable. Example:
2307 testdb=> <userinput>\setenv PAGER less</userinput>
2308 testdb=> <userinput>\setenv LESS -imx4F</userinput>
2309 </programlisting></para>
2314 <term><literal>\sf[+] <replaceable class="parameter">function_description</> </literal></term>
2318 This command fetches and shows the definition of the named function,
2319 in the form of a <command>CREATE OR REPLACE FUNCTION</> command.
2320 The definition is printed to the current query output channel,
2321 as set by <command>\o</command>.
2325 The target function can be specified by name alone, or by name
2326 and arguments, for example <literal>foo(integer, text)</>.
2327 The argument types must be given if there is more
2328 than one function of the same name.
2332 If <literal>+</literal> is appended to the command name, then the
2333 output lines are numbered, with the first line of the function body
2341 <term><literal>\t</literal></term>
2344 Toggles the display of output column name headings and row count
2345 footer. This command is equivalent to <literal>\pset
2346 tuples_only</literal> and is provided for convenience.
2353 <term><literal>\T <replaceable class="parameter">table_options</replaceable></literal></term>
2356 Specifies attributes to be placed within the
2357 <sgmltag>table</sgmltag> tag in <acronym>HTML</acronym>
2358 output format. This command is equivalent to <literal>\pset
2359 tableattr <replaceable
2360 class="parameter">table_options</replaceable></literal>.
2367 <term><literal>\timing [ <replaceable class="parameter">on</replaceable> | <replaceable class="parameter">off</replaceable> ]</literal></term>
2370 Without parameter, toggles a display of how long each SQL statement
2371 takes, in milliseconds. With parameter, sets same.
2378 <term><literal>\unset <replaceable class="parameter">name</replaceable></literal></term>
2382 Unsets (deletes) the <application>psql</> variable <replaceable
2383 class="parameter">name</replaceable>.
2390 <term><literal>\w</literal> <replaceable class="parameter">filename</replaceable></term>
2391 <term><literal>\w</literal> <literal>|</><replaceable class="parameter">command</replaceable></term>
2394 Outputs the current query buffer to the file <replaceable
2395 class="parameter">filename</replaceable> or pipes it to the Unix
2396 command <replaceable class="parameter">command</replaceable>.
2403 <term><literal>\x [ <replaceable class="parameter">on</replaceable> | <replaceable class="parameter">off</replaceable> | <replaceable class="parameter">auto</replaceable> ]</literal></term>
2406 Sets or toggles expanded table formatting mode. As such it is equivalent to
2407 <literal>\pset expanded</literal>.
2414 <term><literal>\z [ <link linkend="APP-PSQL-patterns"><replaceable class="parameter">pattern</replaceable></link> ]</literal></term>
2417 Lists tables, views and sequences with their
2418 associated access privileges.
2419 If a <replaceable class="parameter">pattern</replaceable> is
2420 specified, only tables, views and sequences whose names match the
2425 This is an alias for <command>\dp</command> (<quote>display
2426 privileges</quote>).
2433 <term><literal>\! [ <replaceable class="parameter">command</replaceable> ]</literal></term>
2436 Escapes to a separate Unix shell or executes the Unix command
2437 <replaceable class="parameter">command</replaceable>. The
2438 arguments are not further interpreted; the shell will see them
2446 <term><literal>\?</literal></term>
2449 Shows help information about the backslash commands.
2457 <refsect3 id="APP-PSQL-patterns">
2458 <title id="APP-PSQL-patterns-title">Patterns</title>
2461 <primary>patterns</primary>
2462 <secondary>in psql and pg_dump</secondary>
2466 The various <literal>\d</> commands accept a <replaceable
2467 class="parameter">pattern</replaceable> parameter to specify the
2468 object name(s) to be displayed. In the simplest case, a pattern
2469 is just the exact name of the object. The characters within a
2470 pattern are normally folded to lower case, just as in SQL names;
2471 for example, <literal>\dt FOO</> will display the table named
2472 <literal>foo</>. As in SQL names, placing double quotes around
2473 a pattern stops folding to lower case. Should you need to include
2474 an actual double quote character in a pattern, write it as a pair
2475 of double quotes within a double-quote sequence; again this is in
2476 accord with the rules for SQL quoted identifiers. For example,
2477 <literal>\dt "FOO""BAR"</> will display the table named
2478 <literal>FOO"BAR</> (not <literal>foo"bar</>). Unlike the normal
2479 rules for SQL names, you can put double quotes around just part
2480 of a pattern, for instance <literal>\dt FOO"FOO"BAR</> will display
2481 the table named <literal>fooFOObar</>.
2485 Whenever the <replaceable class="parameter">pattern</replaceable> parameter
2486 is omitted completely, the <literal>\d</> commands display all objects
2487 that are visible in the current schema search path — this is
2488 equivalent to using <literal>*</> as the pattern.
2489 (An object is said to be <firstterm>visible</> if its
2490 containing schema is in the search path and no object of the same
2491 kind and name appears earlier in the search path. This is equivalent to the
2492 statement that the object can be referenced by name without explicit
2493 schema qualification.)
2494 To see all objects in the database regardless of visibility,
2495 use <literal>*.*</> as the pattern.
2499 Within a pattern, <literal>*</> matches any sequence of characters
2500 (including no characters) and <literal>?</> matches any single character.
2501 (This notation is comparable to Unix shell file name patterns.)
2502 For example, <literal>\dt int*</> displays tables whose names
2503 begin with <literal>int</>. But within double quotes, <literal>*</>
2504 and <literal>?</> lose these special meanings and are just matched
2509 A pattern that contains a dot (<literal>.</>) is interpreted as a schema
2510 name pattern followed by an object name pattern. For example,
2511 <literal>\dt foo*.*bar*</> displays all tables whose table name
2512 includes <literal>bar</> that are in schemas whose schema name
2513 starts with <literal>foo</>. When no dot appears, then the pattern
2514 matches only objects that are visible in the current schema search path.
2515 Again, a dot within double quotes loses its special meaning and is matched
2520 Advanced users can use regular-expression notations such as character
2521 classes, for example <literal>[0-9]</> to match any digit. All regular
2522 expression special characters work as specified in
2523 <xref linkend="functions-posix-regexp">, except for <literal>.</> which
2524 is taken as a separator as mentioned above, <literal>*</> which is
2525 translated to the regular-expression notation <literal>.*</>,
2526 <literal>?</> which is translated to <literal>.</>, and
2527 <literal>$</> which is matched literally. You can emulate
2528 these pattern characters at need by writing
2529 <literal>?</> for <literal>.</>,
2530 <literal>(<replaceable class="parameter">R</replaceable>+|)</literal> for
2531 <literal><replaceable class="parameter">R</replaceable>*</literal>, or
2532 <literal>(<replaceable class="parameter">R</replaceable>|)</literal> for
2533 <literal><replaceable class="parameter">R</replaceable>?</literal>.
2534 <literal>$</> is not needed as a regular-expression character since
2535 the pattern must match the whole name, unlike the usual
2536 interpretation of regular expressions (in other words, <literal>$</>
2537 is automatically appended to your pattern). Write <literal>*</> at the
2538 beginning and/or end if you don't wish the pattern to be anchored.
2539 Note that within double quotes, all regular expression special characters
2540 lose their special meanings and are matched literally. Also, the regular
2541 expression special characters are matched literally in operator name
2542 patterns (i.e., the argument of <literal>\do</>).
2548 <title>Advanced Features</title>
2550 <refsect3 id="APP-PSQL-variables">
2551 <title id="APP-PSQL-variables-title">Variables</title>
2554 <application>psql</application> provides variable substitution
2555 features similar to common Unix command shells.
2556 Variables are simply name/value pairs, where the value
2557 can be any string of any length. The name must consist of letters
2558 (including non-Latin letters), digits, and underscores.
2562 To set a variable, use the <application>psql</application> meta-command
2563 <command>\set</command>. For example,
2565 testdb=> <userinput>\set foo bar</userinput>
2567 sets the variable <literal>foo</literal> to the value
2568 <literal>bar</literal>. To retrieve the content of the variable, precede
2569 the name with a colon, for example:
2571 testdb=> <userinput>\echo :foo</userinput>
2574 This works in both regular SQL commands and meta-commands; there is
2575 more detail in <xref linkend="APP-PSQL-interpolation"
2576 endterm="APP-PSQL-interpolation-title">, below.
2580 If you call <command>\set</command> without a second argument, the
2581 variable is set, with an empty string as value. To unset (i.e., delete)
2582 a variable, use the command <command>\unset</command>. To show the
2583 values of all variables, call <command>\set</command> without any argument.
2588 The arguments of <command>\set</command> are subject to the same
2589 substitution rules as with other commands. Thus you can construct
2590 interesting references such as <literal>\set :foo
2591 'something'</literal> and get <quote>soft links</quote> or
2592 <quote>variable variables</quote> of <productname>Perl</productname>
2593 or <productname><acronym>PHP</acronym></productname> fame,
2594 respectively. Unfortunately (or fortunately?), there is no way to do
2595 anything useful with these constructs. On the other hand,
2596 <literal>\set bar :foo</literal> is a perfectly valid way to copy a
2602 A number of these variables are treated specially
2603 by <application>psql</application>. They represent certain option
2604 settings that can be changed at run time by altering the value of
2605 the variable, or in some cases represent changeable state of
2606 <application>psql</application>. Although
2607 you can use these variables for other purposes, this is not
2608 recommended, as the program behavior might grow really strange
2609 really quickly. By convention, all specially treated variables' names
2610 consist of all upper-case ASCII letters (and possibly digits and
2611 underscores). To ensure maximum compatibility in the future, avoid
2612 using such variable names for your own purposes. A list of all specially
2613 treated variables follows.
2619 <primary>autocommit</primary>
2620 <secondary>psql</secondary>
2622 <term><varname>AUTOCOMMIT</varname></term>
2625 When <literal>on</> (the default), each SQL command is automatically
2626 committed upon successful completion. To postpone commit in this
2627 mode, you must enter a <command>BEGIN</> or <command>START
2628 TRANSACTION</> SQL command. When <literal>off</> or unset, SQL
2629 commands are not committed until you explicitly issue
2630 <command>COMMIT</> or <command>END</>. The autocommit-off
2631 mode works by issuing an implicit <command>BEGIN</> for you, just
2632 before any command that is not already in a transaction block and
2633 is not itself a <command>BEGIN</> or other transaction-control
2634 command, nor a command that cannot be executed inside a transaction
2635 block (such as <command>VACUUM</>).
2640 In autocommit-off mode, you must explicitly abandon any failed
2641 transaction by entering <command>ABORT</> or <command>ROLLBACK</>.
2642 Also keep in mind that if you exit the session
2643 without committing, your work will be lost.
2649 The autocommit-on mode is <productname>PostgreSQL</>'s traditional
2650 behavior, but autocommit-off is closer to the SQL spec. If you
2651 prefer autocommit-off, you might wish to set it in the system-wide
2652 <filename>psqlrc</filename> file or your
2653 <filename>~/.psqlrc</filename> file.
2660 <term><varname>DBNAME</varname></term>
2663 The name of the database you are currently connected to. This is
2664 set every time you connect to a database (including program
2665 start-up), but can be unset.
2671 <term><varname>ECHO</varname></term>
2674 If set to <literal>all</literal>, all lines
2675 entered from the keyboard or from a script are written to the standard output
2676 before they are parsed or executed. To select this behavior on program
2677 start-up, use the switch <option>-a</option>. If set to
2678 <literal>queries</literal>,
2679 <application>psql</application> merely prints all queries as
2680 they are sent to the server. The switch for this is
2681 <option>-e</option>.
2687 <term><varname>ECHO_HIDDEN</varname></term>
2690 When this variable is set and a backslash command queries the
2691 database, the query is first shown. This way you can study the
2692 <productname>PostgreSQL</productname> internals and provide
2693 similar functionality in your own programs. (To select this behavior
2694 on program start-up, use the switch <option>-E</option>.) If you set
2695 the variable to the value <literal>noexec</literal>, the queries are
2696 just shown but are not actually sent to the server and executed.
2702 <term><varname>ENCODING</varname></term>
2705 The current client character set encoding.
2711 <term><varname>FETCH_COUNT</varname></term>
2714 If this variable is set to an integer value > 0,
2715 the results of <command>SELECT</command> queries are fetched
2716 and displayed in groups of that many rows, rather than the
2717 default behavior of collecting the entire result set before
2718 display. Therefore only a
2719 limited amount of memory is used, regardless of the size of
2720 the result set. Settings of 100 to 1000 are commonly used
2721 when enabling this feature.
2722 Keep in mind that when using this feature, a query might
2723 fail after having already displayed some rows.
2727 Although you can use any output format with this feature,
2728 the default <literal>aligned</> format tends to look bad
2729 because each group of <varname>FETCH_COUNT</varname> rows
2730 will be formatted separately, leading to varying column
2731 widths across the row groups. The other output formats work better.
2738 <term><varname>HISTCONTROL</varname></term>
2741 If this variable is set to <literal>ignorespace</literal>,
2742 lines which begin with a space are not entered into the history
2743 list. If set to a value of <literal>ignoredups</literal>, lines
2744 matching the previous history line are not entered. A value of
2745 <literal>ignoreboth</literal> combines the two options. If
2746 unset, or if set to any other value than those above, all lines
2747 read in interactive mode are saved on the history list.
2751 This feature was shamelessly plagiarized from
2752 <application>Bash</application>.
2759 <term><varname>HISTFILE</varname></term>
2762 The file name that will be used to store the history list. The default
2763 value is <filename>~/.psql_history</filename>. For example, putting:
2765 \set HISTFILE ~/.psql_history- :DBNAME
2767 in <filename>~/.psqlrc</filename> will cause
2768 <application>psql</application> to maintain a separate history for
2773 This feature was shamelessly plagiarized from
2774 <application>Bash</application>.
2781 <term><varname>HISTSIZE</varname></term>
2784 The number of commands to store in the command history. The
2785 default value is 500.
2789 This feature was shamelessly plagiarized from
2790 <application>Bash</application>.
2797 <term><varname>HOST</varname></term>
2800 The database server host you are currently connected to. This is
2801 set every time you connect to a database (including program
2802 start-up), but can be unset.
2808 <term><varname>IGNOREEOF</varname></term>
2811 If unset, sending an <acronym>EOF</> character (usually
2812 <keycombo action="simul"><keycap>Control</><keycap>D</></>)
2813 to an interactive session of <application>psql</application>
2814 will terminate the application. If set to a numeric value,
2815 that many <acronym>EOF</> characters are ignored before the
2816 application terminates. If the variable is set but has no
2817 numeric value, the default is 10.
2821 This feature was shamelessly plagiarized from
2822 <application>Bash</application>.
2829 <term><varname>LASTOID</varname></term>
2832 The value of the last affected OID, as returned from an
2833 <command>INSERT</command> or <command>\lo_import</command>
2834 command. This variable is only guaranteed to be valid until
2835 after the result of the next <acronym>SQL</acronym> command has
2843 <primary>rollback</primary>
2844 <secondary>psql</secondary>
2846 <term><varname>ON_ERROR_ROLLBACK</varname></term>
2849 When <literal>on</>, if a statement in a transaction block
2850 generates an error, the error is ignored and the transaction
2851 continues. When <literal>interactive</>, such errors are only
2852 ignored in interactive sessions, and not when reading script
2853 files. When <literal>off</> (the default), a statement in a
2854 transaction block that generates an error aborts the entire
2855 transaction. The on_error_rollback-on mode works by issuing an
2856 implicit <command>SAVEPOINT</> for you, just before each command
2857 that is in a transaction block, and rolls back to the savepoint
2864 <term><varname>ON_ERROR_STOP</varname></term>
2867 By default, command processing continues after an error. When this
2868 variable is set, it will instead stop immediately. In interactive mode,
2869 <application>psql</application> will return to the command prompt;
2870 otherwise, <application>psql</application> will exit, returning
2871 error code 3 to distinguish this case from fatal error
2872 conditions, which are reported using error code 1. In either case,
2873 any currently running scripts (the top-level script, if any, and any
2874 other scripts which it may have in invoked) will be terminated
2875 immediately. If the top-level command string contained multiple SQL
2876 commands, processing will stop with the current command.
2882 <term><varname>PORT</varname></term>
2885 The database server port to which you are currently connected.
2886 This is set every time you connect to a database (including
2887 program start-up), but can be unset.
2893 <term><varname>PROMPT1</varname></term>
2894 <term><varname>PROMPT2</varname></term>
2895 <term><varname>PROMPT3</varname></term>
2898 These specify what the prompts <application>psql</application>
2899 issues should look like. See <xref
2900 linkend="APP-PSQL-prompting"
2901 endterm="APP-PSQL-prompting-title"> below.
2907 <term><varname>QUIET</varname></term>
2910 This variable is equivalent to the command line option
2911 <option>-q</option>. It is probably not too useful in
2918 <term><varname>SINGLELINE</varname></term>
2921 This variable is equivalent to the command line option
2922 <option>-S</option>.
2928 <term><varname>SINGLESTEP</varname></term>
2931 This variable is equivalent to the command line option
2932 <option>-s</option>.
2938 <term><varname>USER</varname></term>
2941 The database user you are currently connected as. This is set
2942 every time you connect to a database (including program
2943 start-up), but can be unset.
2949 <term><varname>VERBOSITY</varname></term>
2952 This variable can be set to the values <literal>default</>,
2953 <literal>verbose</>, or <literal>terse</> to control the verbosity
2963 <refsect3 id="APP-PSQL-interpolation">
2964 <title id="APP-PSQL-interpolation-title"><acronym>SQL</acronym> Interpolation</title>
2967 A key feature of <application>psql</application>
2968 variables is that you can substitute (<quote>interpolate</quote>)
2969 them into regular <acronym>SQL</acronym> statements, as well as the
2970 arguments of meta-commands. Furthermore,
2971 <application>psql</application> provides facilities for
2972 ensuring that variable values used as SQL literals and identifiers are
2973 properly quoted. The syntax for interpolating a value without
2974 any quoting is to prepend the variable name with a colon
2975 (<literal>:</literal>). For example,
2977 testdb=> <userinput>\set foo 'my_table'</userinput>
2978 testdb=> <userinput>SELECT * FROM :foo;</userinput>
2980 would query the table <literal>my_table</literal>. Note that this
2981 may be unsafe: the value of the variable is copied literally, so it can
2982 contain unbalanced quotes, or even backslash commands. You must make sure
2983 that it makes sense where you put it.
2987 When a value is to be used as an SQL literal or identifier, it is
2988 safest to arrange for it to be quoted. To quote the value of
2989 a variable as an SQL literal, write a colon followed by the variable
2990 name in single quotes. To quote the value as an SQL identifier, write
2991 a colon followed by the variable name in double quotes.
2992 These constructs deal correctly with quotes and other special
2993 characters embedded within the variable value.
2994 The previous example would be more safely written this way:
2996 testdb=> <userinput>\set foo 'my_table'</userinput>
2997 testdb=> <userinput>SELECT * FROM :"foo";</userinput>
3002 Variable interpolation will not be performed within quoted
3003 <acronym>SQL</acronym> literals and identifiers. Therefore, a
3004 construction such as <literal>':foo'</> doesn't work to produce a quoted
3005 literal from a variable's value (and it would be unsafe if it did work,
3006 since it wouldn't correctly handle quotes embedded in the value).
3010 One example use of this mechanism is to
3011 copy the contents of a file into a table column.
3012 First load the file into a variable and then interpolate the variable's
3013 value as a quoted string:
3015 testdb=> <userinput>\set content `cat my_file.txt`</userinput>
3016 testdb=> <userinput>INSERT INTO my_table VALUES (:'content');</userinput>
3018 (Note that this still won't work if <filename>my_file.txt</filename> contains NUL bytes.
3019 psql does not support embedded NUL bytes in variable values.)
3023 Since colons can legally appear in SQL commands, an apparent attempt
3024 at interpolation (that is, <literal>:name</literal>,
3025 <literal>:'name'</literal>, or <literal>:"name"</literal>) is not
3026 replaced unless the named variable is currently set. In any case, you
3027 can escape a colon with a backslash to protect it from substitution.
3031 The colon syntax for variables is standard <acronym>SQL</acronym> for
3032 embedded query languages, such as <application>ECPG</application>.
3033 The colon syntaxes for array slices and type casts are
3034 <productname>PostgreSQL</productname> extensions, which can sometimes
3035 conflict with the standard usage. The colon-quote syntax for escaping a
3036 variable's value as an SQL literal or identifier is a
3037 <application>psql</application> extension.
3042 <refsect3 id="APP-PSQL-prompting">
3043 <title id="APP-PSQL-prompting-title">Prompting</title>
3046 The prompts <application>psql</application> issues can be customized
3047 to your preference. The three variables <varname>PROMPT1</varname>,
3048 <varname>PROMPT2</varname>, and <varname>PROMPT3</varname> contain strings
3049 and special escape sequences that describe the appearance of the
3050 prompt. Prompt 1 is the normal prompt that is issued when
3051 <application>psql</application> requests a new command. Prompt 2 is
3052 issued when more input is expected during command input because the
3053 command was not terminated with a semicolon or a quote was not closed.
3054 Prompt 3 is issued when you run an <acronym>SQL</acronym>
3055 <command>COPY</command> command and you are expected to type in the
3056 row values on the terminal.
3060 The value of the selected prompt variable is printed literally,
3061 except where a percent sign (<literal>%</literal>) is encountered.
3062 Depending on the next character, certain other text is substituted
3063 instead. Defined substitutions are:
3067 <term><literal>%M</literal></term>
3070 The full host name (with domain name) of the database server,
3071 or <literal>[local]</literal> if the connection is over a Unix
3073 <literal>[local:<replaceable>/dir/name</replaceable>]</literal>,
3074 if the Unix domain socket is not at the compiled in default
3081 <term><literal>%m</literal></term>
3084 The host name of the database server, truncated at the
3085 first dot, or <literal>[local]</literal> if the connection is
3086 over a Unix domain socket.
3092 <term><literal>%></literal></term>
3093 <listitem><para>The port number at which the database server is listening.</para></listitem>
3097 <term><literal>%n</literal></term>
3100 The database session user name. (The expansion of this
3101 value might change during a database session as the result
3102 of the command <command>SET SESSION
3103 AUTHORIZATION</command>.)
3109 <term><literal>%/</literal></term>
3110 <listitem><para>The name of the current database.</para></listitem>
3114 <term><literal>%~</literal></term>
3115 <listitem><para>Like <literal>%/</literal>, but the output is <literal>~</literal>
3116 (tilde) if the database is your default database.</para></listitem>
3120 <term><literal>%#</literal></term>
3123 If the session user is a database superuser, then a
3124 <literal>#</literal>, otherwise a <literal>></literal>.
3125 (The expansion of this value might change during a database
3126 session as the result of the command <command>SET SESSION
3127 AUTHORIZATION</command>.)
3133 <term><literal>%R</literal></term>
3136 In prompt 1 normally <literal>=</literal>, but <literal>^</literal> if
3137 in single-line mode, and <literal>!</literal> if the session is
3138 disconnected from the database (which can happen if
3139 <command>\connect</command> fails). In prompt 2 the sequence is
3140 replaced by <literal>-</literal>, <literal>*</literal>, a single quote,
3141 a double quote, or a dollar sign, depending on whether
3142 <application>psql</application> expects more input because the
3143 command wasn't terminated yet, because you are inside a
3144 <literal>/* ... */</literal> comment, or because you are inside
3145 a quoted or dollar-escaped string. In prompt 3 the sequence doesn't
3152 <term><literal>%x</literal></term>
3155 Transaction status: an empty string when not in a transaction
3156 block, or <literal>*</> when in a transaction block, or
3157 <literal>!</> when in a failed transaction block, or <literal>?</>
3158 when the transaction state is indeterminate (for example, because
3159 there is no connection).
3165 <term><literal>%</literal><replaceable class="parameter">digits</replaceable></term>
3168 The character with the indicated octal code is substituted.
3174 <term><literal>%:</literal><replaceable class="parameter">name</replaceable><literal>:</literal></term>
3177 The value of the <application>psql</application> variable
3178 <replaceable class="parameter">name</replaceable>. See the
3179 section <xref linkend="APP-PSQL-variables"
3180 endterm="APP-PSQL-variables-title"> for details.
3186 <term><literal>%`</literal><replaceable class="parameter">command</replaceable><literal>`</literal></term>
3189 The output of <replaceable
3190 class="parameter">command</replaceable>, similar to ordinary
3191 <quote>back-tick</quote> substitution.
3197 <term><literal>%[</literal> ... <literal>%]</literal></term>
3200 Prompts can contain terminal control characters which, for
3201 example, change the color, background, or style of the prompt
3202 text, or change the title of the terminal window. In order for
3203 the line editing features of <application>Readline</application> to work properly, these
3204 non-printing control characters must be designated as invisible
3205 by surrounding them with <literal>%[</literal> and
3206 <literal>%]</literal>. Multiple pairs of these can occur within
3207 the prompt. For example:
3209 testdb=> \set PROMPT1 '%[%033[1;33;40m%]%n@%/%R%[%033[0m%]%# '
3211 results in a boldfaced (<literal>1;</literal>) yellow-on-black
3212 (<literal>33;40</literal>) prompt on VT100-compatible, color-capable
3220 To insert a percent sign into your prompt, write
3221 <literal>%%</literal>. The default prompts are
3222 <literal>'%/%R%# '</literal> for prompts 1 and 2, and
3223 <literal>'>> '</literal> for prompt 3.
3228 This feature was shamelessly plagiarized from
3229 <application>tcsh</application>.
3236 <title>Command-Line Editing</title>
3239 <application>psql</application> supports the <application>Readline</application>
3240 library for convenient line editing and retrieval. The command
3241 history is automatically saved when <application>psql</application>
3242 exits and is reloaded when
3243 <application>psql</application> starts up. Tab-completion is also
3244 supported, although the completion logic makes no claim to be an
3245 <acronym>SQL</acronym> parser. If for some reason you do not like the tab completion, you
3246 can turn it off by putting this in a file named
3247 <filename>.inputrc</filename> in your home directory:
3250 set disable-completion on
3253 (This is not a <application>psql</application> but a
3254 <application>Readline</application> feature. Read its documentation
3255 for further details.)
3262 <refsect1 id="app-psql-environment">
3263 <title id="app-psql-environment-title">Environment</title>
3268 <term><envar>COLUMNS</envar></term>
3272 If <literal>\pset columns</> is zero, controls the
3273 width for the <literal>wrapped</> format and width for determining
3274 if wide output requires the pager or should be switched to the
3275 vertical format in expanded auto mode.
3281 <term><envar>PAGER</envar></term>
3285 If the query results do not fit on the screen, they are piped
3286 through this command. Typical values are
3287 <literal>more</literal> or <literal>less</literal>. The default
3288 is platform-dependent. The use of the pager can be disabled by
3289 using the <command>\pset</command> command.
3295 <term><envar>PGDATABASE</envar></term>
3296 <term><envar>PGHOST</envar></term>
3297 <term><envar>PGPORT</envar></term>
3298 <term><envar>PGUSER</envar></term>
3302 Default connection parameters (see <xref linkend="libpq-envars">).
3308 <term><envar>PSQL_EDITOR</envar></term>
3309 <term><envar>EDITOR</envar></term>
3310 <term><envar>VISUAL</envar></term>
3314 Editor used by the <command>\e</command> and
3315 <command>\ef</command> commands. The variables are examined in
3316 the order listed; the first that is set is used.
3320 The built-in default editors are <filename>vi</filename> on Unix
3321 systems and <filename>notepad.exe</filename> on Windows systems.
3327 <term><envar>PSQL_EDITOR_LINENUMBER_ARG</envar></term>
3331 When <command>\e</command> or <command>\ef</command> is used
3332 with a line number argument, this variable specifies the
3333 command-line argument used to pass the starting line number to
3334 the user's editor. For editors such as <productname>Emacs</> or
3335 <productname>vi</>, this is a plus sign. Include a trailing
3336 space in the value of the variable if there needs to be space
3337 between the option name and the line number. Examples:
3339 PSQL_EDITOR_LINENUMBER_ARG='+'
3340 PSQL_EDITOR_LINENUMBER_ARG='--line '
3345 The default is <literal>+</literal> on Unix systems
3346 (corresponding to the default editor <filename>vi</filename>,
3347 and useful for many other common editors); but there is no
3348 default on Windows systems.
3354 <term><envar>PSQL_HISTORY</envar></term>
3358 Alternative location for the command history file. Tilde ("~") expansion is performed.
3364 <term><envar>PSQLRC</envar></term>
3368 Alternative location of the user's .psqlrc file. Tilde ("~") expansion is performed.
3374 <term><envar>SHELL</envar></term>
3378 Command executed by the <command>\!</command> command.
3384 <term><envar>TMPDIR</envar></term>
3388 Directory for storing temporary files. The default is
3389 <filename>/tmp</filename>.
3396 This utility, like most other <productname>PostgreSQL</> utilities,
3397 also uses the environment variables supported by <application>libpq</>
3398 (see <xref linkend="libpq-envars">).
3405 <title>Files</title>
3410 Unless it is passed an <option>-X</option>
3411 or <option>-c</option> option,
3412 <application>psql</application> attempts to
3413 read and execute commands from the system-wide
3414 <filename>psqlrc</filename> file and the user's
3415 <filename>~/.psqlrc</filename> file before starting up.
3416 (On Windows, the user's startup file is named
3417 <filename>%APPDATA%\postgresql\psqlrc.conf</filename>.)
3418 See <filename><replaceable>PREFIX</>/share/psqlrc.sample</>
3419 for information on setting up the system-wide file. It could be used
3420 to set up the client or the server to taste (using the <command>\set
3421 </command> and <command>SET</command> commands).
3424 The location of the user's <filename>~/.psqlrc</filename> file can
3425 also be set explicitly via the <envar>PSQLRC</envar> environment
3432 Both the system-wide <filename>psqlrc</filename> file and the user's
3433 <filename>~/.psqlrc</filename> file can be made version-specific
3434 by appending a dash and the <productname>PostgreSQL</productname>
3435 major or minor <application>psql</application> release number,
3436 for example <filename>~/.psqlrc-9.2</filename> or
3437 <filename>~/.psqlrc-9.2.5</filename>. The most specific
3438 version-matching file will be read in preference to a
3439 non-version-specific file.
3445 The command-line history is stored in the file
3446 <filename>~/.psql_history</filename>, or
3447 <filename>%APPDATA%\postgresql\psql_history</filename> on Windows.
3450 The location of the history file can
3451 also be set explicitly via the <envar>PSQL_HISTORY</envar> environment
3460 <title>Notes</title>
3465 In an earlier life <application>psql</application> allowed the
3466 first argument of a single-letter backslash command to start
3467 directly after the command, without intervening whitespace.
3468 As of <productname>PostgreSQL</productname> 8.4 this is no
3474 <para><application>psql</application> is only guaranteed to work smoothly
3475 with servers of the same version. That does not mean other combinations
3476 will fail outright, but subtle and not-so-subtle problems might come
3477 up. Backslash commands are particularly likely to fail if the
3478 server is of a newer version than <application>psql</> itself. However,
3479 backslash commands of the <literal>\d</> family should work with
3480 servers of versions back to 7.4, though not necessarily with servers
3481 newer than <application>psql</> itself.
3490 <title>Notes for Windows Users</title>
3493 <application>psql</application> is built as a <quote>console
3494 application</>. Since the Windows console windows use a different
3495 encoding than the rest of the system, you must take special care
3496 when using 8-bit characters within <application>psql</application>.
3497 If <application>psql</application> detects a problematic
3498 console code page, it will warn you at startup. To change the
3499 console code page, two things are necessary:
3504 Set the code page by entering <userinput>cmd.exe /c chcp
3505 1252</userinput>. (1252 is a code page that is appropriate for
3506 German; replace it with your value.) If you are using Cygwin,
3507 you can put this command in <filename>/etc/profile</filename>.
3513 Set the console font to <literal>Lucida Console</>, because the
3514 raster font does not work with the ANSI code page.
3517 </itemizedlist></para>
3522 <refsect1 id="APP-PSQL-examples">
3523 <title id="APP-PSQL-examples-title">Examples</title>
3526 The first example shows how to spread a command over several lines of
3527 input. Notice the changing prompt:
3529 testdb=> <userinput>CREATE TABLE my_table (</userinput>
3530 testdb(> <userinput> first integer not null default 0,</userinput>
3531 testdb(> <userinput> second text)</userinput>
3532 testdb-> <userinput>;</userinput>
3535 Now look at the table definition again:
3537 testdb=> <userinput>\d my_table</userinput>
3539 Attribute | Type | Modifier
3540 -----------+---------+--------------------
3541 first | integer | not null default 0
3545 Now we change the prompt to something more interesting:
3547 testdb=> <userinput>\set PROMPT1 '%n@%m %~%R%# '</userinput>
3548 peter@localhost testdb=>
3550 Let's assume you have filled the table with data and want to take a
3553 peter@localhost testdb=> SELECT * FROM my_table;
3563 You can display tables in different ways by using the
3564 <command>\pset</command> command:
3566 peter@localhost testdb=> <userinput>\pset border 2</userinput>
3568 peter@localhost testdb=> <userinput>SELECT * FROM my_table;</userinput>
3579 peter@localhost testdb=> <userinput>\pset border 0</userinput>
3581 peter@localhost testdb=> <userinput>SELECT * FROM my_table;</userinput>
3590 peter@localhost testdb=> <userinput>\pset border 1</userinput>
3592 peter@localhost testdb=> <userinput>\pset format unaligned</userinput>
3593 Output format is unaligned.
3594 peter@localhost testdb=> <userinput>\pset fieldsep ","</userinput>
3595 Field separator is ",".
3596 peter@localhost testdb=> <userinput>\pset tuples_only</userinput>
3597 Showing only tuples.
3598 peter@localhost testdb=> <userinput>SELECT second, first FROM my_table;</userinput>
3604 Alternatively, use the short commands:
3606 peter@localhost testdb=> <userinput>\a \t \x</userinput>
3607 Output format is aligned.
3609 Expanded display is on.
3610 peter@localhost testdb=> <userinput>SELECT * FROM my_table;</userinput>
3623 </programlisting></para>