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. Also, only
103 the result of the last SQL command is returned.
109 <term><option>-d <replaceable class="parameter">dbname</replaceable></></term>
110 <term><option>--dbname=<replaceable class="parameter">dbname</replaceable></></term>
113 Specifies the name of the database to connect to. This is
114 equivalent to specifying <replaceable
115 class="parameter">dbname</replaceable> as the first non-option
116 argument on the command line.
119 If this parameter contains an <symbol>=</symbol> sign or starts
120 with a valid <acronym>URI</acronym> prefix
121 (<literal>postgresql://</literal>
122 or <literal>postgres://</literal>), it is treated as a
123 <parameter>conninfo</parameter> string. See <xref
124 linkend="libpq-connstring"> for more information.
130 <term><option>-e</></term>
131 <term><option>--echo-queries</></term>
134 Copy all SQL commands sent to the server to standard output as well.
136 to setting the variable <varname>ECHO</varname> to
137 <literal>queries</literal>.
143 <term><option>-E</></term>
144 <term><option>--echo-hidden</></term>
147 Echo the actual queries generated by <command>\d</command> and other backslash
148 commands. You can use this to study <application>psql</application>'s
149 internal operations. This is equivalent to
150 setting the variable <varname>ECHO_HIDDEN</varname> from within
151 <application>psql</application>.
157 <term><option>-f <replaceable class="parameter">filename</replaceable></></term>
158 <term><option>--file=<replaceable class="parameter">filename</replaceable></></term>
161 Use the file <replaceable class="parameter">filename</replaceable>
162 as the source of commands instead of reading commands interactively.
163 After the file is processed, <application>psql</application>
164 terminates. This is in many ways equivalent to the meta-command
165 <command>\i</command>.
169 If <replaceable>filename</replaceable> is <literal>-</literal>
170 (hyphen), then standard input is read.
174 Using this option is subtly different from writing <literal>psql
176 class="parameter">filename</replaceable></literal>. In general,
177 both will do what you expect, but using <literal>-f</literal>
178 enables some nice features such as error messages with line
179 numbers. There is also a slight chance that using this option will
180 reduce the start-up overhead. On the other hand, the variant using
181 the shell's input redirection is (in theory) guaranteed to yield
182 exactly the same output you would have received had you entered
189 <term><option>-F <replaceable class="parameter">separator</replaceable></></term>
190 <term><option>--field-separator=<replaceable class="parameter">separator</replaceable></></term>
193 Use <replaceable class="parameter">separator</replaceable> as the
194 field separator for unaligned output. This is equivalent to
195 <command>\pset fieldsep</command> or <command>\f</command>.
201 <term><option>-h <replaceable class="parameter">hostname</replaceable></></term>
202 <term><option>--host=<replaceable class="parameter">hostname</replaceable></></term>
205 Specifies the host name of the machine on which the
206 server is running. If the value begins
207 with a slash, it is used as the directory for the Unix-domain
214 <term><option>-H</></term>
215 <term><option>--html</></term>
218 Turn on <acronym>HTML</acronym> tabular output. This is
219 equivalent to <literal>\pset format html</literal> or the
220 <command>\H</command> command.
226 <term><option>-l</></term>
227 <term><option>--list</></term>
230 List all available databases, then exit. Other non-connection
231 options are ignored. This is similar to the meta-command
232 <command>\list</command>.
238 <term><option>-L <replaceable class="parameter">filename</replaceable></></term>
239 <term><option>--log-file=<replaceable class="parameter">filename</replaceable></></term>
242 Write all query output into file <replaceable
243 class="parameter">filename</replaceable>, in addition to the
244 normal output destination.
250 <term><option>-n</></term>
251 <term><option>--no-readline</></term>
254 Do not use <application>readline</application> for line editing and do not use the history.
255 This can be useful to turn off tab expansion when cutting and pasting.
261 <term><option>-o <replaceable class="parameter">filename</replaceable></></term>
262 <term><option>--output=<replaceable class="parameter">filename</replaceable></></term>
265 Put all query output into file <replaceable
266 class="parameter">filename</replaceable>. This is equivalent to
267 the command <command>\o</command>.
273 <term><option>-p <replaceable class="parameter">port</replaceable></></term>
274 <term><option>--port=<replaceable class="parameter">port</replaceable></></term>
277 Specifies the TCP port or the local Unix-domain
278 socket file extension on which the server is listening for
279 connections. Defaults to the value of the <envar>PGPORT</envar>
280 environment variable or, if not set, to the port specified at
281 compile time, usually 5432.
287 <term><option>-P <replaceable class="parameter">assignment</replaceable></></term>
288 <term><option>--pset=<replaceable class="parameter">assignment</replaceable></></term>
291 Specifies printing options, in the style of
292 <command>\pset</command>. Note that here you
293 have to separate name and value with an equal sign instead of a
294 space. For example, to set the output format to <application>LaTeX</application>, you could write
295 <literal>-P format=latex</literal>.
301 <term><option>-q</></term>
302 <term><option>--quiet</></term>
305 Specifies that <application>psql</application> should do its work
306 quietly. By default, it prints welcome messages and various
307 informational output. If this option is used, none of this
308 happens. This is useful with the <option>-c</option> option.
309 Within <application>psql</application> you can also set the
310 <varname>QUIET</varname> variable to achieve the same effect.
316 <term><option>-R <replaceable class="parameter">separator</replaceable></></term>
317 <term><option>--record-separator=<replaceable class="parameter">separator</replaceable></></term>
320 Use <replaceable class="parameter">separator</replaceable> as the
321 record separator for unaligned output. This is equivalent to the
322 <command>\pset recordsep</command> command.
328 <term><option>-s</></term>
329 <term><option>--single-step</></term>
332 Run in single-step mode. That means the user is prompted before
333 each command is sent to the server, with the option to cancel
334 execution as well. Use this to debug scripts.
340 <term><option>-S</></term>
341 <term><option>--single-line</></term>
344 Runs in single-line mode where a newline terminates an SQL command, as a
350 This mode is provided for those who insist on it, but you are not
351 necessarily encouraged to use it. In particular, if you mix
352 <acronym>SQL</acronym> and meta-commands on a line the order of
353 execution might not always be clear to the inexperienced user.
360 <term><option>-t</></term>
361 <term><option>--tuples-only</></term>
364 Turn off printing of column names and result row count footers,
365 etc. This is equivalent to the <command>\t</command> command.
371 <term><option>-T <replaceable class="parameter">table_options</replaceable></></term>
372 <term><option>--table-attr=<replaceable class="parameter">table_options</replaceable></></term>
375 Specifies options to be placed within the
376 <acronym>HTML</acronym> <sgmltag>table</sgmltag> tag. See
377 <command>\pset</command> for details.
383 <term><option>-U <replaceable class="parameter">username</replaceable></></term>
384 <term><option>--username=<replaceable class="parameter">username</replaceable></></term>
387 Connect to the database as the user <replaceable
388 class="parameter">username</replaceable> instead of the default.
389 (You must have permission to do so, of course.)
395 <term><option>-v <replaceable class="parameter">assignment</replaceable></></term>
396 <term><option>--set=<replaceable class="parameter">assignment</replaceable></></term>
397 <term><option>--variable=<replaceable class="parameter">assignment</replaceable></></term>
400 Perform a variable assignment, like the <command>\set</command>
401 meta-command. Note that you must separate name and value, if
402 any, by an equal sign on the command line. To unset a variable,
403 leave off the equal sign. To set a variable with an empty value,
404 use the equal sign but leave off the value. These assignments are
405 done during a very early stage of start-up, so variables reserved
406 for internal purposes might get overwritten later.
412 <term><option>-V</></term>
413 <term><option>--version</></term>
416 Print the <application>psql</application> version and exit.
422 <term><option>-w</></term>
423 <term><option>--no-password</></term>
426 Never issue a password prompt. If the server requires password
427 authentication and a password is not available by other means
428 such as a <filename>.pgpass</filename> file, the connection
429 attempt will fail. This option can be useful in batch jobs and
430 scripts where no user is present to enter a password.
434 Note that this option will remain set for the entire session,
435 and so it affects uses of the meta-command
436 <command>\connect</command> as well as the initial connection attempt.
442 <term><option>-W</></term>
443 <term><option>--password</></term>
446 Force <application>psql</application> to prompt for a
447 password before connecting to a database.
451 This option is never essential, since <application>psql</application>
452 will automatically prompt for a password if the server demands
453 password authentication. However, <application>psql</application>
454 will waste a connection attempt finding out that the server wants a
455 password. In some cases it is worth typing <option>-W</> to avoid
456 the extra connection attempt.
460 Note that this option will remain set for the entire session,
461 and so it affects uses of the meta-command
462 <command>\connect</command> as well as the initial connection attempt.
468 <term><option>-x</></term>
469 <term><option>--expanded</></term>
472 Turn on the expanded table formatting mode. This is equivalent to the
473 <command>\x</command> command.
479 <term><option>-X,</></term>
480 <term><option>--no-psqlrc</></term>
483 Do not read the start-up file (neither the system-wide
484 <filename>psqlrc</filename> file nor the user's
485 <filename>~/.psqlrc</filename> file).
491 <term><option>-z</option></term>
492 <term><option>--field-separator-zero</option></term>
495 Set the field separator for unaligned output to a zero byte.
501 <term><option>-0</option></term>
502 <term><option>--record-separator-zero</option></term>
505 Set the record separator for unaligned output to a zero byte. This is
506 useful for interfacing, for example, with <literal>xargs -0</literal>.
512 <term><option>-1</option></term>
513 <term><option>--single-transaction</option></term>
516 When <application>psql</application> executes a script, adding
517 this option wraps <command>BEGIN</>/<command>COMMIT</> around the
518 script to execute it as a single transaction. This ensures that
519 either all the commands complete successfully, or no changes are
524 If the script itself uses <command>BEGIN</>, <command>COMMIT</>,
525 or <command>ROLLBACK</>, this option will not have the desired
527 Also, if the script contains any command that cannot be executed
528 inside a transaction block, specifying this option will cause that
529 command (and hence the whole transaction) to fail.
535 <term><option>-?</></term>
536 <term><option>--help</></term>
539 Show help about <application>psql</application> command line
550 <title>Exit Status</title>
553 <application>psql</application> returns 0 to the shell if it
554 finished normally, 1 if a fatal error of its own occurs (e.g. out of memory,
555 file not found), 2 if the connection to the server went bad
556 and the session was not interactive, and 3 if an error occurred in a
557 script and the variable <varname>ON_ERROR_STOP</varname> was set.
565 <refsect2 id="R2-APP-PSQL-connecting">
566 <title>Connecting to a Database</title>
569 <application>psql</application> is a regular
570 <productname>PostgreSQL</productname> client application. In order
571 to connect to a database you need to know the name of your target
572 database, the host name and port number of the server, and what user
573 name you want to connect as. <application>psql</application> can be
574 told about those parameters via command line options, namely
575 <option>-d</option>, <option>-h</option>, <option>-p</option>, and
576 <option>-U</option> respectively. If an argument is found that does
577 not belong to any option it will be interpreted as the database name
578 (or the user name, if the database name is already given). Not all
579 of these options are required; there are useful defaults. If you omit the host
580 name, <application>psql</> will connect via a Unix-domain socket
581 to a server on the local host, or via TCP/IP to <literal>localhost</> on
582 machines that don't have Unix-domain sockets. The default port number is
583 determined at compile time.
584 Since the database server uses the same default, you will not have
585 to specify the port in most cases. The default user name is your
586 Unix user name, as is the default database name. Note that you cannot
587 just connect to any database under any user name. Your database
588 administrator should have informed you about your access rights.
592 When the defaults aren't quite right, you can save yourself
593 some typing by setting the environment variables
594 <envar>PGDATABASE</envar>, <envar>PGHOST</envar>,
595 <envar>PGPORT</envar> and/or <envar>PGUSER</envar> to appropriate
596 values. (For additional environment variables, see <xref
597 linkend="libpq-envars">.) It is also convenient to have a
598 <filename>~/.pgpass</> file to avoid regularly having to type in
599 passwords. See <xref linkend="libpq-pgpass"> for more information.
603 An alternative way to specify connection parameters is in a
604 <parameter>conninfo</parameter> string or
605 a <acronym>URI</acronym>, which is used instead of a database
606 name. This mechanism give you very wide control over the
607 connection. For example:
609 $ <userinput>psql "service=myservice sslmode=require"</userinput>
610 $ <userinput>psql postgresql://dbmaster:5433/mydb?sslmode=require</userinput>
612 This way you can also use <acronym>LDAP</acronym> for connection
613 parameter lookup as described in <xref linkend="libpq-ldap">.
614 See <xref linkend="libpq-paramkeywords"> for more information on all the
615 available connection options.
619 If the connection could not be made for any reason (e.g., insufficient
620 privileges, server is not running on the targeted host, etc.),
621 <application>psql</application> will return an error and terminate.
625 If at least one of standard input or standard output are a
626 terminal, then <application>psql</application> sets the client
627 encoding to <quote>auto</quote>, which will detect the
628 appropriate client encoding from the locale settings
629 (<envar>LC_CTYPE</envar> environment variable on Unix systems).
630 If this doesn't work out as expected, the client encoding can be
631 overridden using the environment
632 variable <envar>PGCLIENTENCODING</envar>.
636 <refsect2 id="R2-APP-PSQL-4">
637 <title>Entering SQL Commands</title>
640 In normal operation, <application>psql</application> provides a
641 prompt with the name of the database to which
642 <application>psql</application> is currently connected, followed by
643 the string <literal>=></literal>. For example:
645 $ <userinput>psql testdb</userinput>
647 Type "help" for help.
654 At the prompt, the user can type in <acronym>SQL</acronym> commands.
655 Ordinarily, input lines are sent to the server when a
656 command-terminating semicolon is reached. An end of line does not
657 terminate a command. Thus commands can be spread over several lines for
658 clarity. If the command was sent and executed without error, the results
659 of the command are displayed on the screen.
663 Whenever a command is executed, <application>psql</application> also polls
664 for asynchronous notification events generated by
665 <xref linkend="SQL-LISTEN"> and
666 <xref linkend="SQL-NOTIFY">.
670 <refsect2 id="APP-PSQL-meta-commands">
671 <title>Meta-Commands</title>
674 Anything you enter in <application>psql</application> that begins
675 with an unquoted backslash is a <application>psql</application>
676 meta-command that is processed by <application>psql</application>
677 itself. These commands make
678 <application>psql</application> more useful for administration or
679 scripting. Meta-commands are often called slash or backslash commands.
683 The format of a <application>psql</application> command is the backslash,
684 followed immediately by a command verb, then any arguments. The arguments
685 are separated from the command verb and each other by any number of
686 whitespace characters.
690 To include whitespace in an argument you can quote it with
691 single quotes. To include a single quote in an argument,
692 write two single quotes within single-quoted text.
693 Anything contained in single quotes is
694 furthermore subject to C-like substitutions for
695 <literal>\n</literal> (new line), <literal>\t</literal> (tab),
696 <literal>\b</literal> (backspace), <literal>\r</literal> (carriage return),
697 <literal>\f</literal> (form feed),
698 <literal>\</literal><replaceable>digits</replaceable> (octal), and
699 <literal>\x</literal><replaceable>digits</replaceable> (hexadecimal).
700 A backslash preceding any other character within single-quoted text
701 quotes that single character, whatever it is.
705 Within an argument, text that is enclosed in backquotes
706 (<literal>`</literal>) is taken as a command line that is passed to the
707 shell. The output of the command (with any trailing newline removed)
708 replaces the backquoted text.
712 If an unquoted colon (<literal>:</literal>) followed by a
713 <application>psql</> variable name appears within an argument, it is
714 replaced by the variable's value, as described in <xref
715 linkend="APP-PSQL-interpolation" endterm="APP-PSQL-interpolation-title">.
719 Some commands take an <acronym>SQL</acronym> identifier (such as a
720 table name) as argument. These arguments follow the syntax rules
721 of <acronym>SQL</acronym>: Unquoted letters are forced to
722 lowercase, while double quotes (<literal>"</>) protect letters
723 from case conversion and allow incorporation of whitespace into
724 the identifier. Within double quotes, paired double quotes reduce
725 to a single double quote in the resulting name. For example,
726 <literal>FOO"BAR"BAZ</> is interpreted as <literal>fooBARbaz</>,
727 and <literal>"A weird"" name"</> becomes <literal>A weird"
732 Parsing for arguments stops at the end of the line, or when another
733 unquoted backslash is found. An unquoted backslash
734 is taken as the beginning of a new meta-command. The special
735 sequence <literal>\\</literal> (two backslashes) marks the end of
736 arguments and continues parsing <acronym>SQL</acronym> commands, if
737 any. That way <acronym>SQL</acronym> and
738 <application>psql</application> commands can be freely mixed on a
739 line. But in any case, the arguments of a meta-command cannot
740 continue beyond the end of the line.
744 The following meta-commands are defined:
748 <term><literal>\a</literal></term>
751 If the current table output format is unaligned, it is switched to aligned.
752 If it is not unaligned, it is set to unaligned. This command is
753 kept for backwards compatibility. See <command>\pset</command> for a
754 more general solution.
760 <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>
763 Establishes a new connection to a <productname>PostgreSQL</>
764 server. If the new connection is successfully made, the
765 previous connection is closed. If any of <replaceable
766 class="parameter">dbname</replaceable>, <replaceable
767 class="parameter">username</replaceable>, <replaceable
768 class="parameter">host</replaceable> or <replaceable
769 class="parameter">port</replaceable> are omitted or specified
770 as <literal>-</literal>, the value of that parameter from the
771 previous connection is used. If there is no previous
772 connection, the <application>libpq</application> default for
773 the parameter's value is used.
777 If the connection attempt failed (wrong user name, access
778 denied, etc.), the previous connection will only be kept if
779 <application>psql</application> is in interactive mode. When
780 executing a non-interactive script, processing will
781 immediately stop with an error. This distinction was chosen as
782 a user convenience against typos on the one hand, and a safety
783 mechanism that scripts are not accidentally acting on the
784 wrong database on the other hand.
790 <term><literal>\C [ <replaceable class="parameter">title</replaceable> ]</literal></term>
793 Sets the title of any tables being printed as the result of a
794 query or unset any such title. This command is equivalent to
795 <literal>\pset title <replaceable
796 class="parameter">title</replaceable></literal>. (The name of
797 this command derives from <quote>caption</quote>, as it was
798 previously only used to set the caption in an
799 <acronym>HTML</acronym> table.)
805 <term><literal>\cd [ <replaceable>directory</replaceable> ]</literal></term>
808 Changes the current working directory to
809 <replaceable>directory</replaceable>. Without argument, changes
810 to the current user's home directory.
815 To print your current working directory, use <literal>\! pwd</literal>.
822 <term><literal>\conninfo</literal></term>
825 Outputs information about the current database connection.
830 <varlistentry id="APP-PSQL-meta-commands-copy">
831 <term><literal>\copy { <replaceable class="parameter">table</replaceable> [ ( <replaceable class="parameter">column_list</replaceable> ) ] | ( <replaceable class="parameter">query</replaceable> ) }
832 { <literal>from</literal> | <literal>to</literal> }
833 { <replaceable class="parameter">'filename'</replaceable> | program <replaceable class="parameter">'command'</replaceable> | stdin | stdout | pstdin | pstdout }
834 [ [ with ] ( <replaceable class="parameter">option</replaceable> [, ...] ) ]</literal></term>
838 Performs a frontend (client) copy. This is an operation that
839 runs an <acronym>SQL</acronym> <xref linkend="SQL-COPY">
840 command, but instead of the server
841 reading or writing the specified file,
842 <application>psql</application> reads or writes the file and
843 routes the data between the server and the local file system.
844 This means that file accessibility and privileges are those of
845 the local user, not the server, and no SQL superuser
846 privileges are required.
850 When <literal>program</> is specified,
851 <replaceable class="parameter">command</replaceable> is
852 executed by <application>psql</application> and the data from
853 or to <replaceable class="parameter">command</replaceable> is
854 routed between the server and the client.
855 This means that the execution privileges are those of
856 the local user, not the server, and no SQL superuser
857 privileges are required.
860 <para><literal>\copy ... from stdin | to stdout</literal>
861 reads/writes based on the command input and output respectively.
862 All rows are read from the same source that issued the command,
863 continuing until <literal>\.</literal> is read or the stream
864 reaches <acronym>EOF</>. Output is sent to the same place as
865 command output. To read/write from
866 <application>psql</application>'s standard input or output, use
867 <literal>pstdin</> or <literal>pstdout</>. This option is useful
868 for populating tables in-line within a SQL script file.
872 The syntax of the command is similar to that of the
873 <acronym>SQL</acronym> <xref linkend="sql-copy">
875 <replaceable class="parameter">option</replaceable>
876 must indicate one of the options of the
877 <acronym>SQL</acronym> <xref linkend="sql-copy"> command.
878 Note that, because of this,
879 special parsing rules apply to the <command>\copy</command>
880 command. In particular, the variable substitution rules and
881 backslash escapes do not apply.
886 This operation is not as efficient as the <acronym>SQL</acronym>
887 <command>COPY</command> command because all data must pass
888 through the client/server connection. For large
889 amounts of data the <acronym>SQL</acronym> command might be preferable.
897 <term><literal>\copyright</literal></term>
900 Shows the copyright and distribution terms of
901 <productname>PostgreSQL</productname>.
907 <term><literal>\d[S+] [ <link linkend="APP-PSQL-patterns"><replaceable class="parameter">pattern</replaceable></link> ]</literal></term>
911 For each relation (table, view, index, sequence, or foreign table)
912 or composite type matching the
913 <replaceable class="parameter">pattern</replaceable>, show all
914 columns, their types, the tablespace (if not the default) and any
915 special attributes such as <literal>NOT NULL</literal> or defaults.
916 Associated indexes, constraints, rules, and triggers are
917 also shown. For foreign tables, the associated foreign
918 server is shown as well.
919 (<quote>Matching the pattern</> is defined in
920 <xref linkend="APP-PSQL-patterns" endterm="APP-PSQL-patterns-title">
925 For some types of relation, <literal>\d</> shows additional information
926 for each column: column values for sequences, indexed expression for
927 indexes and foreign data wrapper options for foreign tables.
931 The command form <literal>\d+</literal> is identical, except that
932 more information is displayed: any comments associated with the
933 columns of the table are shown, as is the presence of OIDs in the
934 table, the view definition if the relation is a view.
938 By default, only user-created objects are shown; supply a
939 pattern or the <literal>S</literal> modifier to include system
945 If <command>\d</command> is used without a
946 <replaceable class="parameter">pattern</replaceable> argument, it is
947 equivalent to <command>\dtvsE</command> which will show a list of
948 all visible tables, views, sequences and foreign tables.
949 This is purely a convenience measure.
956 <term><literal>\da[S] [ <link linkend="APP-PSQL-patterns"><replaceable class="parameter">pattern</replaceable></link> ]</literal></term>
960 Lists aggregate functions, together with their
961 return type and the data types they operate on. If <replaceable
962 class="parameter">pattern</replaceable>
963 is specified, only aggregates whose names match the pattern are shown.
964 By default, only user-created objects are shown; supply a
965 pattern or the <literal>S</literal> modifier to include system
973 <term><literal>\db[+] [ <link linkend="APP-PSQL-patterns"><replaceable class="parameter">pattern</replaceable></link> ]</literal></term>
977 Lists tablespaces. If <replaceable
978 class="parameter">pattern</replaceable>
979 is specified, only tablespaces whose names match the pattern are shown.
980 If <literal>+</literal> is appended to the command name, each object
981 is listed with its associated permissions.
988 <term><literal>\dc[S+] [ <link linkend="APP-PSQL-patterns"><replaceable class="parameter">pattern</replaceable></link> ]</literal></term>
991 Lists conversions between character-set encodings.
992 If <replaceable class="parameter">pattern</replaceable>
993 is specified, only conversions whose names match the pattern are
995 By default, only user-created objects are shown; supply a
996 pattern or the <literal>S</literal> modifier to include system
998 If <literal>+</literal> is appended to the command name, each object
999 is listed with its associated description.
1006 <term><literal>\dC[+] [ <link linkend="APP-PSQL-patterns"><replaceable class="parameter">pattern</replaceable></link> ]</literal></term>
1010 If <replaceable class="parameter">pattern</replaceable>
1011 is specified, only casts whose source or target types match the
1013 If <literal>+</literal> is appended to the command name, each object
1014 is listed with its associated description.
1021 <term><literal>\dd[S] [ <link linkend="APP-PSQL-patterns"><replaceable class="parameter">pattern</replaceable></link> ]</literal></term>
1024 Shows the descriptions of objects of type <literal>constraint</>,
1025 <literal>operator class</>, <literal>operator family</>,
1026 <literal>rule</>, and <literal>trigger</>. All
1027 other comments may be viewed by the respective backslash commands for
1031 <para><literal>\dd</literal> displays descriptions for objects matching the
1032 <replaceable class="parameter">pattern</replaceable>, or of visible
1033 objects of the appropriate type if no argument is given. But in either
1034 case, only objects that have a description are listed.
1035 By default, only user-created objects are shown; supply a
1036 pattern or the <literal>S</literal> modifier to include system
1041 Descriptions for objects can be created with the <xref
1042 linkend="sql-comment">
1043 <acronym>SQL</acronym> command.
1050 <term><literal>\ddp [ <link linkend="APP-PSQL-patterns"><replaceable class="parameter">pattern</replaceable></link> ]</literal></term>
1053 Lists default access privilege settings. An entry is shown for
1054 each role (and schema, if applicable) for which the default
1055 privilege settings have been changed from the built-in defaults.
1056 If <replaceable class="parameter">pattern</replaceable> is
1057 specified, only entries whose role name or schema name matches
1058 the pattern are listed.
1062 The <xref linkend="sql-alterdefaultprivileges"> command is used to set
1063 default access privileges. The meaning of the
1064 privilege display is explained under
1065 <xref linkend="sql-grant">.
1072 <term><literal>\dD[S+] [ <link linkend="APP-PSQL-patterns"><replaceable class="parameter">pattern</replaceable></link> ]</literal></term>
1075 Lists domains. If <replaceable
1076 class="parameter">pattern</replaceable>
1077 is specified, only domains whose names match the pattern are shown.
1078 By default, only user-created objects are shown; supply a
1079 pattern or the <literal>S</literal> modifier to include system
1081 If <literal>+</literal> is appended to the command name, each object
1082 is listed with its associated permissions and description.
1089 <term><literal>\dE[S+] [ <link linkend="APP-PSQL-patterns"><replaceable class="parameter">pattern</replaceable></link> ]</literal></term>
1090 <term><literal>\di[S+] [ <link linkend="APP-PSQL-patterns"><replaceable class="parameter">pattern</replaceable></link> ]</literal></term>
1091 <term><literal>\ds[S+] [ <link linkend="APP-PSQL-patterns"><replaceable class="parameter">pattern</replaceable></link> ]</literal></term>
1092 <term><literal>\dt[S+] [ <link linkend="APP-PSQL-patterns"><replaceable class="parameter">pattern</replaceable></link> ]</literal></term>
1093 <term><literal>\dv[S+] [ <link linkend="APP-PSQL-patterns"><replaceable class="parameter">pattern</replaceable></link> ]</literal></term>
1097 In this group of commands, the letters <literal>E</literal>,
1098 <literal>i</literal>, <literal>s</literal>,
1099 <literal>t</literal>, and <literal>v</literal>
1100 stand for foreign table, index, sequence, table, and view,
1102 You can specify any or all of
1103 these letters, in any order, to obtain a listing of objects
1104 of these types. For example, <literal>\dit</> lists indexes
1105 and tables. If <literal>+</literal> is
1106 appended to the command name, each object is listed with its
1107 physical size on disk and its associated description, if any.
1108 If <replaceable class="parameter">pattern</replaceable> is
1109 specified, only objects whose names match the pattern are listed.
1110 By default, only user-created objects are shown; supply a
1111 pattern or the <literal>S</literal> modifier to include system
1119 <term><literal>\des[+] [ <link linkend="APP-PSQL-patterns"><replaceable class="parameter">pattern</replaceable></link> ]</literal></term>
1122 Lists foreign servers (mnemonic: <quote>external
1124 If <replaceable class="parameter">pattern</replaceable> is
1125 specified, only those servers whose name matches the pattern
1126 are listed. If the form <literal>\des+</literal> is used, a
1127 full description of each server is shown, including the
1128 server's ACL, type, version, options, and description.
1135 <term><literal>\det[+] [ <link linkend="APP-PSQL-patterns"><replaceable class="parameter">pattern</replaceable></link> ]</literal></term>
1138 Lists foreign tables (mnemonic: <quote>external tables</quote>).
1139 If <replaceable class="parameter">pattern</replaceable> is
1140 specified, only entries whose table name or schema name matches
1141 the pattern are listed. If the form <literal>\det+</literal>
1142 is used, generic options and the foreign table description
1150 <term><literal>\deu[+] [ <link linkend="APP-PSQL-patterns"><replaceable class="parameter">pattern</replaceable></link> ]</literal></term>
1153 Lists user mappings (mnemonic: <quote>external
1155 If <replaceable class="parameter">pattern</replaceable> is
1156 specified, only those mappings whose user names match the
1157 pattern are listed. If the form <literal>\deu+</literal> is
1158 used, additional information about each mapping is shown.
1163 <literal>\deu+</literal> might also display the user name and
1164 password of the remote user, so care should be taken not to
1173 <term><literal>\dew[+] [ <link linkend="APP-PSQL-patterns"><replaceable class="parameter">pattern</replaceable></link> ]</literal></term>
1176 Lists foreign-data wrappers (mnemonic: <quote>external
1178 If <replaceable class="parameter">pattern</replaceable> is
1179 specified, only those foreign-data wrappers whose name matches
1180 the pattern are listed. If the form <literal>\dew+</literal>
1181 is used, the ACL, options, and description of the foreign-data
1182 wrapper are also shown.
1189 <term><literal>\df[antwS+] [ <link linkend="APP-PSQL-patterns"><replaceable class="parameter">pattern</replaceable></link> ]</literal></term>
1193 Lists functions, together with their arguments, return types, and
1194 function types, which are classified as <quote>agg</> (aggregate),
1195 <quote>normal</>, <quote>trigger</>, or <quote>window</>.
1196 To display only functions
1197 of specific type(s), add the corresponding letters <literal>a</>,
1198 <literal>n</>, <literal>t</>, or <literal>w</> to the command.
1200 class="parameter">pattern</replaceable> is specified, only
1201 functions whose names match the pattern are shown. If the
1202 form <literal>\df+</literal> is used, additional information
1203 about each function, including security, volatility, language, source
1204 code and description, is shown. By default, only user-created
1205 objects are shown; supply a pattern or the <literal>S</literal>
1206 modifier to include system objects.
1211 To look up functions taking arguments or returning values of a specific
1212 type, use your pager's search capability to scroll through the
1213 <literal>\df</> output.
1221 <term><literal>\dF[+] [ <link linkend="APP-PSQL-patterns"><replaceable class="parameter">pattern</replaceable></link> ]</literal></term>
1224 Lists text search configurations.
1225 If <replaceable class="parameter">pattern</replaceable> is specified,
1226 only configurations whose names match the pattern are shown.
1227 If the form <literal>\dF+</literal> is used, a full description of
1228 each configuration is shown, including the underlying text search
1229 parser and the dictionary list for each parser token type.
1235 <term><literal>\dFd[+] [ <link linkend="APP-PSQL-patterns"><replaceable class="parameter">pattern</replaceable></link> ]</literal></term>
1238 Lists text search dictionaries.
1239 If <replaceable class="parameter">pattern</replaceable> is specified,
1240 only dictionaries whose names match the pattern are shown.
1241 If the form <literal>\dFd+</literal> is used, additional information
1242 is shown about each selected dictionary, including the underlying
1243 text search template and the option values.
1249 <term><literal>\dFp[+] [ <link linkend="APP-PSQL-patterns"><replaceable class="parameter">pattern</replaceable></link> ]</literal></term>
1252 Lists text search parsers.
1253 If <replaceable class="parameter">pattern</replaceable> is specified,
1254 only parsers whose names match the pattern are shown.
1255 If the form <literal>\dFp+</literal> is used, a full description of
1256 each parser is shown, including the underlying functions and the
1257 list of recognized token types.
1263 <term><literal>\dFt[+] [ <link linkend="APP-PSQL-patterns"><replaceable class="parameter">pattern</replaceable></link> ]</literal></term>
1266 Lists text search templates.
1267 If <replaceable class="parameter">pattern</replaceable> is specified,
1268 only templates whose names match the pattern are shown.
1269 If the form <literal>\dFt+</literal> is used, additional information
1270 is shown about each template, including the underlying function names.
1277 <term><literal>\dg[+] [ <link linkend="APP-PSQL-patterns"><replaceable class="parameter">pattern</replaceable></link> ]</literal></term>
1280 Lists database roles.
1281 (Since the concepts of <quote>users</> and <quote>groups</> have been
1282 unified into <quote>roles</>, this command is now equivalent to
1283 <literal>\du</literal>.)
1284 If <replaceable class="parameter">pattern</replaceable> is specified,
1285 only those roles whose names match the pattern are listed.
1286 If the form <literal>\dg+</literal> is used, additional information
1287 is shown about each role; currently this adds the comment for each
1295 <term><literal>\dl</literal></term>
1298 This is an alias for <command>\lo_list</command>, which shows a
1299 list of large objects.
1305 <term><literal>\dL[S+] [ <link linkend="APP-PSQL-patterns"><replaceable class="parameter">pattern</replaceable></link> ]</literal></term>
1308 Lists procedural languages. If <replaceable
1309 class="parameter">pattern</replaceable>
1310 is specified, only languages whose names match the pattern are listed.
1311 By default, only user-created languages
1312 are shown; supply the <literal>S</literal> modifier to include system
1313 objects. If <literal>+</literal> is appended to the command name, each
1314 language is listed with its call handler, validator, access privileges,
1315 and whether it is a system object.
1322 <term><literal>\dn[S+] [ <link linkend="APP-PSQL-patterns"><replaceable class="parameter">pattern</replaceable></link> ]</literal></term>
1326 Lists schemas (namespaces). If <replaceable
1327 class="parameter">pattern</replaceable>
1328 is specified, only schemas whose names match the pattern are listed.
1329 By default, only user-created objects are shown; supply a
1330 pattern or the <literal>S</literal> modifier to include system objects.
1331 If <literal>+</literal> is appended to the command name, each object
1332 is listed with its associated permissions and description, if any.
1339 <term><literal>\do[S] [ <link linkend="APP-PSQL-patterns"><replaceable class="parameter">pattern</replaceable></link> ]</literal></term>
1342 Lists operators with their operand and return types.
1343 If <replaceable class="parameter">pattern</replaceable> is
1344 specified, only operators whose names match the pattern are listed.
1345 By default, only user-created objects are shown; supply a
1346 pattern or the <literal>S</literal> modifier to include system
1354 <term><literal>\dO[S+] [ <link linkend="APP-PSQL-patterns"><replaceable class="parameter">pattern</replaceable></link> ]</literal></term>
1358 If <replaceable class="parameter">pattern</replaceable> is
1359 specified, only collations whose names match the pattern are
1360 listed. By default, only user-created objects are shown;
1361 supply a pattern or the <literal>S</literal> modifier to
1362 include system objects. If <literal>+</literal> is appended
1363 to the command name, each collation is listed with its associated
1364 description, if any.
1365 Note that only collations usable with the current database's encoding
1366 are shown, so the results may vary in different databases of the
1374 <term><literal>\dp [ <link linkend="APP-PSQL-patterns"><replaceable class="parameter">pattern</replaceable></link> ]</literal></term>
1377 Lists tables, views and sequences with their
1378 associated access privileges.
1379 If <replaceable class="parameter">pattern</replaceable> is
1380 specified, only tables, views and sequences whose names match the
1385 The <xref linkend="sql-grant"> and
1386 <xref linkend="sql-revoke">
1387 commands are used to set access privileges. The meaning of the
1388 privilege display is explained under
1389 <xref linkend="sql-grant">.
1395 <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>
1398 Lists defined configuration settings. These settings can be
1399 role-specific, database-specific, or both.
1400 <replaceable>role-pattern</replaceable> and
1401 <replaceable>database-pattern</replaceable> are used to select
1402 specific roles and databases to list, respectively. If omitted, or if
1403 <literal>*</> is specified, all settings are listed, including those
1404 not role-specific or database-specific, respectively.
1408 The <xref linkend="sql-alterrole"> and
1409 <xref linkend="sql-alterdatabase">
1410 commands are used to define per-role and per-database configuration
1417 <term><literal>\dT[S+] [ <link linkend="APP-PSQL-patterns"><replaceable class="parameter">pattern</replaceable></link> ]</literal></term>
1421 If <replaceable class="parameter">pattern</replaceable> is
1422 specified, only types whose names match the pattern are listed.
1423 If <literal>+</literal> is appended to the command name, each type is
1424 listed with its internal name and size, its allowed values
1425 if it is an <type>enum</> type, and its associated permissions.
1426 By default, only user-created objects are shown; supply a
1427 pattern or the <literal>S</literal> modifier to include system
1434 <term><literal>\du[+] [ <link linkend="APP-PSQL-patterns"><replaceable class="parameter">pattern</replaceable></link> ]</literal></term>
1437 Lists database roles.
1438 (Since the concepts of <quote>users</> and <quote>groups</> have been
1439 unified into <quote>roles</>, this command is now equivalent to
1440 <literal>\dg</literal>.)
1441 If <replaceable class="parameter">pattern</replaceable> is specified,
1442 only those roles whose names match the pattern are listed.
1443 If the form <literal>\du+</literal> is used, additional information
1444 is shown about each role; currently this adds the comment for each
1451 <term><literal>\dx[+] [ <link linkend="APP-PSQL-patterns"><replaceable class="parameter">pattern</replaceable></link> ]</literal></term>
1454 Lists installed extensions.
1455 If <replaceable class="parameter">pattern</replaceable>
1456 is specified, only those extensions whose names match the pattern
1458 If the form <literal>\dx+</literal> is used, all the objects belonging
1459 to each matching extension are listed.
1465 <term><literal>\dy[+] [ <link linkend="APP-PSQL-patterns"><replaceable class="parameter">pattern</replaceable></link> ]</literal></term>
1468 Lists event triggers.
1469 If <replaceable class="parameter">pattern</replaceable>
1470 is specified, only those event triggers whose names match the pattern
1472 If <literal>+</literal> is appended to the command name, each object
1473 is listed with its associated description.
1479 <term><literal>\e</literal> or <literal>\edit</> <literal> <optional> <replaceable class="parameter">filename</> </optional> <optional> <replaceable class="parameter">line_number</> </optional> </literal></term>
1483 If <replaceable class="parameter">filename</replaceable> is
1484 specified, the file is edited; after the editor exits, its
1485 content is copied back to the query buffer. If no <replaceable
1486 class="parameter">filename</replaceable> is given, the current query
1487 buffer is copied to a temporary file which is then edited in the same
1492 The new query buffer is then re-parsed according to the normal
1493 rules of <application>psql</application>, where the whole buffer
1494 is treated as a single line. (Thus you cannot make scripts this
1495 way. Use <command>\i</command> for that.) This means that
1496 if the query ends with (or contains) a semicolon, it is
1497 immediately executed. Otherwise it will merely wait in the
1498 query buffer; type semicolon or <literal>\g</> to send it, or
1499 <literal>\r</> to cancel.
1503 If a line number is specified, <application>psql</application> will
1504 position the cursor on the specified line of the file or query buffer.
1505 Note that if a single all-digits argument is given,
1506 <application>psql</application> assumes it is a line number,
1512 See under <xref linkend="app-psql-environment"
1513 endterm="app-psql-environment-title"> for how to configure and
1514 customize your editor.
1521 <term><literal>\echo <replaceable class="parameter">text</replaceable> [ ... ]</literal></term>
1524 Prints the arguments to the standard output, separated by one
1525 space and followed by a newline. This can be useful to
1526 intersperse information in the output of scripts. For example:
1528 => <userinput>\echo `date`</userinput>
1529 Tue Oct 26 21:40:57 CEST 1999
1531 If the first argument is an unquoted <literal>-n</literal> the trailing
1532 newline is not written.
1537 If you use the <command>\o</command> command to redirect your
1538 query output you might wish to use <command>\qecho</command>
1539 instead of this command.
1546 <term><literal>\ef <optional> <replaceable class="parameter">function_description</> <optional> <replaceable class="parameter">line_number</> </optional> </optional> </literal></term>
1550 This command fetches and edits the definition of the named function,
1551 in the form of a <command>CREATE OR REPLACE FUNCTION</> command.
1552 Editing is done in the same way as for <literal>\edit</>.
1553 After the editor exits, the updated command waits in the query buffer;
1554 type semicolon or <literal>\g</> to send it, or <literal>\r</>
1559 The target function can be specified by name alone, or by name
1560 and arguments, for example <literal>foo(integer, text)</>.
1561 The argument types must be given if there is more
1562 than one function of the same name.
1566 If no function is specified, a blank <command>CREATE FUNCTION</>
1567 template is presented for editing.
1571 If a line number is specified, <application>psql</application> will
1572 position the cursor on the specified line of the function body.
1573 (Note that the function body typically does not begin on the first
1579 See under <xref linkend="app-psql-environment"
1580 endterm="app-psql-environment-title"> for how to configure and
1581 customize your editor.
1589 <term><literal>\encoding [ <replaceable class="parameter">encoding</replaceable> ]</literal></term>
1593 Sets the client character set encoding. Without an argument, this command
1594 shows the current encoding.
1601 <term><literal>\f [ <replaceable class="parameter">string</replaceable> ]</literal></term>
1605 Sets the field separator for unaligned query output. The default
1606 is the vertical bar (<literal>|</literal>). See also
1607 <command>\pset</command> for a generic way of setting output
1615 <term><literal>\g</literal> [ { <replaceable class="parameter">filename</replaceable> | <literal>|</literal><replaceable class="parameter">command</replaceable> } ]</term>
1619 Sends the current query input buffer to the server and
1620 optionally stores the query's output in <replaceable
1621 class="parameter">filename</replaceable> or pipes the output
1622 into a separate Unix shell executing <replaceable
1623 class="parameter">command</replaceable>. The file or command is
1624 written to only if the query successfully returns zero or more tuples,
1625 not if the query fails or is a non-data-returning SQL command.
1628 A bare <literal>\g</literal> is essentially equivalent to a semicolon.
1629 A <literal>\g</literal> with argument is a <quote>one-shot</quote>
1630 alternative to the <command>\o</command> command.
1636 <term><literal>\gset</literal> [ <replaceable class="parameter">prefix</replaceable> ]</term>
1640 Sends the current query input buffer to the server and stores the
1641 query's output into <application>psql</> variables (see <xref
1642 linkend="APP-PSQL-variables" endterm="APP-PSQL-variables-title">).
1643 The query to be executed must return exactly one row. Each column of
1644 the row is stored into a separate variable, named the same as the
1645 column. For example:
1647 => <userinput>SELECT 'hello' AS var1, 10 AS var2</userinput>
1648 -> <userinput>\gset</userinput>
1649 => <userinput>\echo :var1 :var2</userinput>
1654 If you specify a <replaceable class="parameter">prefix</replaceable>,
1655 that string is prepended to the query's column names to create the
1656 variable names to use:
1658 => <userinput>SELECT 'hello' AS var1, 10 AS var2</userinput>
1659 -> <userinput>\gset result_</userinput>
1660 => <userinput>\echo :result_var1 :result_var2</userinput>
1665 If a column result is NULL, the corresponding variable is unset
1666 rather than being set.
1669 If the query fails or does not return one row,
1670 no variables are changed.
1676 <term><literal>\h</literal> or <literal>\help</literal> <literal>[ <replaceable class="parameter">command</replaceable> ]</literal></term>
1679 Gives syntax help on the specified <acronym>SQL</acronym>
1680 command. If <replaceable class="parameter">command</replaceable>
1681 is not specified, then <application>psql</application> will list
1682 all the commands for which syntax help is available. If
1683 <replaceable class="parameter">command</replaceable> is an
1684 asterisk (<literal>*</literal>), then syntax help on all
1685 <acronym>SQL</acronym> commands is shown.
1690 To simplify typing, commands that consists of several words do
1691 not have to be quoted. Thus it is fine to type <userinput>\help
1692 alter table</userinput>.
1700 <term><literal>\H</literal></term>
1703 Turns on <acronym>HTML</acronym> query output format. If the
1704 <acronym>HTML</acronym> format is already on, it is switched
1705 back to the default aligned text format. This command is for
1706 compatibility and convenience, but see <command>\pset</command>
1707 about setting other output options.
1714 <term><literal>\i <replaceable class="parameter">filename</replaceable></literal></term>
1717 Reads input from the file <replaceable
1718 class="parameter">filename</replaceable> and executes it as
1719 though it had been typed on the keyboard.
1723 If you want to see the lines on the screen as they are read you
1724 must set the variable <varname>ECHO</varname> to
1725 <literal>all</literal>.
1733 <term><literal>\ir <replaceable class="parameter">filename</replaceable></literal></term>
1736 The <literal>\ir</> command is similar to <literal>\i</>, but resolves
1737 relative file names differently. When executing in interactive mode,
1738 the two commands behave identically. However, when invoked from a
1739 script, <literal>\ir</literal> interprets file names relative to the
1740 directory in which the script is located, rather than the current
1748 <term><literal>\l</literal> (or <literal>\list</literal>)</term>
1749 <term><literal>\l+</literal> (or <literal>\list+</literal>)</term>
1752 List the names, owners, character set encodings, and access privileges
1753 of all the databases in the server.
1754 If <literal>+</literal> is appended to the command name, database
1755 sizes, default tablespaces, and descriptions are also displayed.
1756 (Size information is only available for databases that the current
1757 user can connect to.)
1764 <term><literal>\lo_export <replaceable class="parameter">loid</replaceable> <replaceable class="parameter">filename</replaceable></literal></term>
1768 Reads the large object with <acronym>OID</acronym> <replaceable
1769 class="parameter">loid</replaceable> from the database and
1770 writes it to <replaceable
1771 class="parameter">filename</replaceable>. Note that this is
1772 subtly different from the server function
1773 <function>lo_export</function>, which acts with the permissions
1774 of the user that the database server runs as and on the server's
1779 Use <command>\lo_list</command> to find out the large object's
1780 <acronym>OID</acronym>.
1788 <term><literal>\lo_import <replaceable class="parameter">filename</replaceable> [ <replaceable class="parameter">comment</replaceable> ]</literal></term>
1792 Stores the file into a <productname>PostgreSQL</productname>
1793 large object. Optionally, it associates the given
1794 comment with the object. Example:
1796 foo=> <userinput>\lo_import '/home/peter/pictures/photo.xcf' 'a picture of me'</userinput>
1799 The response indicates that the large object received object
1800 ID 152801, which can be used to access the newly-created large
1801 object in the future. For the sake of readability, it is
1802 recommended to always associate a human-readable comment with
1803 every object. Both OIDs and comments can be viewed with the
1804 <command>\lo_list</command> command.
1808 Note that this command is subtly different from the server-side
1809 <function>lo_import</function> because it acts as the local user
1810 on the local file system, rather than the server's user and file
1817 <term><literal>\lo_list</literal></term>
1820 Shows a list of all <productname>PostgreSQL</productname>
1821 large objects currently stored in the database,
1822 along with any comments provided for them.
1828 <term><literal>\lo_unlink <replaceable class="parameter">loid</replaceable></literal></term>
1832 Deletes the large object with <acronym>OID</acronym>
1833 <replaceable class="parameter">loid</replaceable> from the
1839 Use <command>\lo_list</command> to find out the large object's
1840 <acronym>OID</acronym>.
1848 <term><literal>\o</literal> [ {<replaceable class="parameter">filename</replaceable> | <literal>|</literal><replaceable class="parameter">command</replaceable>} ]</term>
1852 Saves future query results to the file <replaceable
1853 class="parameter">filename</replaceable> or pipes future results
1854 into a separate Unix shell to execute <replaceable
1855 class="parameter">command</replaceable>. If no arguments are
1856 specified, the query output will be reset to the standard output.
1859 <para><quote>Query results</quote> includes all tables, command
1860 responses, and notices obtained from the database server, as
1861 well as output of various backslash commands that query the
1862 database (such as <command>\d</command>), but not error
1868 To intersperse text output in between query results, use
1869 <command>\qecho</command>.
1877 <term><literal>\p</literal></term>
1880 Print the current query buffer to the standard output.
1886 <term><literal>\password [ <replaceable class="parameter">username</replaceable> ]</literal></term>
1889 Changes the password of the specified user (by default, the current
1890 user). This command prompts for the new password, encrypts it, and
1891 sends it to the server as an <command>ALTER ROLE</> command. This
1892 makes sure that the new password does not appear in cleartext in the
1893 command history, the server log, or elsewhere.
1899 <term><literal>\prompt [ <replaceable class="parameter">text</replaceable> ] <replaceable class="parameter">name</replaceable></literal></term>
1902 Prompts the user to supply text, which is assigned to the variable
1903 <replaceable class="parameter">name</>.
1904 An optional prompt string, <replaceable
1905 class="parameter">text</>, can be specified. (For multiword
1906 prompts, surround the text with single quotes.)
1910 By default, <literal>\prompt</> uses the terminal for input and
1911 output. However, if the <option>-f</> command line switch was
1912 used, <literal>\prompt</> uses standard input and standard output.
1918 <term><literal>\pset <replaceable class="parameter">option</replaceable> [ <replaceable class="parameter">value</replaceable> ]</literal></term>
1922 This command sets options affecting the output of query result tables.
1923 <replaceable class="parameter">option</replaceable>
1924 indicates which option is to be set. The semantics of
1925 <replaceable class="parameter">value</replaceable> vary depending
1926 on the selected option. For some options, omitting <replaceable
1927 class="parameter">value</replaceable> causes the option to be toggled
1928 or unset, as described under the particular option. If no such
1929 behavior is mentioned, then omitting
1930 <replaceable class="parameter">value</replaceable> just results in
1931 the current setting being displayed.
1935 Adjustable printing options are:
1938 <term><literal>border</literal></term>
1941 The <replaceable class="parameter">value</replaceable> must be a
1942 number. In general, the higher
1943 the number the more borders and lines the tables will have,
1944 but this depends on the particular format. In
1945 <acronym>HTML</acronym> format, this will translate directly
1946 into the <literal>border=...</literal> attribute; in the
1947 other formats only values 0 (no border), 1 (internal dividing lines),
1948 and 2 (table frame) make sense.
1949 <literal>latex</literal> and <literal>latex-longtable</literal>
1950 also support a <literal>border</literal> value of 3 which adds
1951 a dividing line between each row.
1957 <term><literal>columns</literal></term>
1960 Sets the target width for the <literal>wrapped</> format, and also
1961 the width limit for determining whether output is wide enough to
1962 require the pager or switch to the vertical display in expanded auto
1964 Zero (the default) causes the target width to be controlled by the
1965 environment variable <envar>COLUMNS</>, or the detected screen width
1966 if <envar>COLUMNS</> is not set.
1967 In addition, if <literal>columns</> is zero then the
1968 <literal>wrapped</> format only affects screen output.
1969 If <literal>columns</> is nonzero then file and pipe output is
1970 wrapped to that width as well.
1976 <term><literal>expanded</literal> (or <literal>x</literal>)</term>
1979 If <replaceable class="parameter">value</replaceable> is specified it
1980 must be either <literal>on</literal> or <literal>off</literal>, which
1981 will enable or disable expanded mode, or <literal>auto</literal>.
1982 If <replaceable class="parameter">value</replaceable> is omitted the
1983 command toggles between the on and off settings. When expanded mode
1984 is enabled, query results are displayed in two columns, with the
1985 column name on the left and the data on the right. This mode is
1986 useful if the data wouldn't fit on the screen in the
1987 normal <quote>horizontal</quote> mode. In the auto setting, the
1988 expanded mode is used whenever the query output is wider than the
1989 screen, otherwise the regular mode is used. The auto setting is only
1990 effective in the aligned and wrapped formats. In other formats, it
1991 always behaves as if the expanded mode is off.
1997 <term><literal>fieldsep</literal></term>
2000 Specifies the field separator to be used in unaligned output
2001 format. That way one can create, for example, tab- or
2002 comma-separated output, which other programs might prefer. To
2003 set a tab as field separator, type <literal>\pset fieldsep
2004 '\t'</literal>. The default field separator is
2005 <literal>'|'</literal> (a vertical bar).
2011 <term><literal>fieldsep_zero</literal></term>
2014 Sets the field separator to use in unaligned output format to a zero
2021 <term><literal>footer</literal></term>
2024 If <replaceable class="parameter">value</replaceable> is specified
2025 it must be either <literal>on</literal> or <literal>off</literal>
2026 which will enable or disable display of the table footer
2027 (the <literal>(<replaceable>n</> rows)</literal> count).
2028 If <replaceable class="parameter">value</replaceable> is omitted the
2029 command toggles footer display on or off.
2035 <term><literal>format</literal></term>
2038 Sets the output format to one of <literal>unaligned</literal>,
2039 <literal>aligned</literal>, <literal>wrapped</literal>,
2040 <literal>html</literal>,
2041 <literal>latex</literal> (uses <literal>tabular</literal>),
2042 <literal>latex-longtable</literal>, or
2043 <literal>troff-ms</literal>.
2044 Unique abbreviations are allowed. (That would mean one letter
2048 <para><literal>unaligned</> format writes all columns of a row on one
2049 line, separated by the currently active field separator. This
2050 is useful for creating output that might be intended to be read
2051 in by other programs (for example, tab-separated or comma-separated
2055 <para><literal>aligned</literal> format is the standard, human-readable,
2056 nicely formatted text output; this is the default.
2059 <para><literal>wrapped</> format is like <literal>aligned</> but wraps
2060 wide data values across lines to make the output fit in the target
2061 column width. The target width is determined as described under
2062 the <literal>columns</> option. Note that <application>psql</> will
2063 not attempt to wrap column header titles; therefore,
2064 <literal>wrapped</> format behaves the same as <literal>aligned</>
2065 if the total width needed for column headers exceeds the target.
2069 The <literal>html</>, <literal>latex</>,
2070 <literal>latex-longtable</literal>, and <literal>troff-ms</>
2071 formats put out tables that are intended to
2072 be included in documents using the respective mark-up
2073 language. They are not complete documents! This might not be
2074 necessary in <acronym>HTML</acronym>, but in
2075 <application>LaTeX</application> you must have a complete
2076 document wrapper. <literal>latex-longtable</literal>
2077 also requires the <application>LaTeX</application>
2078 <literal>longtable</literal> and <literal>booktabs</> packages.
2084 <term><literal>linestyle</literal></term>
2087 Sets the border line drawing style to one
2088 of <literal>ascii</literal>, <literal>old-ascii</literal>
2089 or <literal>unicode</literal>.
2090 Unique abbreviations are allowed. (That would mean one
2092 The default setting is <literal>ascii</>.
2093 This option only affects the <literal>aligned</> and
2094 <literal>wrapped</> output formats.
2097 <para><literal>ascii</literal> style uses plain <acronym>ASCII</acronym>
2098 characters. Newlines in data are shown using
2099 a <literal>+</literal> symbol in the right-hand margin.
2100 When the <literal>wrapped</literal> format wraps data from
2101 one line to the next without a newline character, a dot
2102 (<literal>.</>) is shown in the right-hand margin of the first line,
2103 and again in the left-hand margin of the following line.
2106 <para><literal>old-ascii</literal> style uses plain <acronym>ASCII</>
2107 characters, using the formatting style used
2108 in <productname>PostgreSQL</productname> 8.4 and earlier.
2109 Newlines in data are shown using a <literal>:</literal>
2110 symbol in place of the left-hand column separator.
2111 When the data is wrapped from one line
2112 to the next without a newline character, a <literal>;</>
2113 symbol is used in place of the left-hand column separator.
2116 <para><literal>unicode</literal> style uses Unicode box-drawing characters.
2117 Newlines in data are shown using a carriage return symbol
2118 in the right-hand margin. When the data is wrapped from one line
2119 to the next without a newline character, an ellipsis symbol
2120 is shown in the right-hand margin of the first line, and
2121 again in the left-hand margin of the following line.
2125 When the <literal>border</> setting is greater than zero,
2126 this option also determines the characters
2127 with which the border lines are drawn.
2128 Plain <acronym>ASCII</acronym> characters work everywhere, but
2129 Unicode characters look nicer on displays that recognize them.
2135 <term><literal>null</literal></term>
2138 Sets the string to be printed in place of a null value.
2139 The default is to print nothing, which can easily be mistaken for
2140 an empty string. For example, one might prefer <literal>\pset null
2147 <term><literal>numericlocale</literal></term>
2150 If <replaceable class="parameter">value</replaceable> is specified
2151 it must be either <literal>on</literal> or <literal>off</literal>
2152 which will enable or disable display of a locale-specific character
2153 to separate groups of digits to the left of the decimal marker.
2154 If <replaceable class="parameter">value</replaceable> is omitted the
2155 command toggles between regular and locale-specific numeric output.
2161 <term><literal>pager</literal></term>
2164 Controls use of a pager program for query and <application>psql</>
2165 help output. If the environment variable <envar>PAGER</envar>
2166 is set, the output is piped to the specified program.
2167 Otherwise a platform-dependent default (such as
2168 <filename>more</filename>) is used.
2172 When the <literal>pager</> option is <literal>off</>, the pager
2173 program is not used. When the <literal>pager</> option is
2174 <literal>on</>, the pager is used when appropriate, i.e., when the
2175 output is to a terminal and will not fit on the screen.
2176 The <literal>pager</> option can also be set to <literal>always</>,
2177 which causes the pager to be used for all terminal output regardless
2178 of whether it fits on the screen. <literal>\pset pager</>
2179 without a <replaceable class="parameter">value</replaceable>
2180 toggles pager use on and off.
2186 <term><literal>recordsep</literal></term>
2189 Specifies the record (line) separator to use in unaligned
2190 output format. The default is a newline character.
2196 <term><literal>recordsep_zero</literal></term>
2199 Sets the record separator to use in unaligned output format to a zero
2206 <term><literal>tableattr</literal> (or <literal>T</literal>)</term>
2209 In <acronym>HTML</acronym> format, this specifies attributes
2210 to be placed inside the <sgmltag>table</sgmltag> tag. This
2211 could for example be <literal>cellpadding</literal> or
2212 <literal>bgcolor</literal>. Note that you probably don't want
2213 to specify <literal>border</literal> here, as that is already
2214 taken care of by <literal>\pset border</literal>.
2216 <replaceable class="parameter">value</replaceable> is given,
2217 the table attributes are unset.
2220 In <literal>latex-longtable</literal> format, this controls
2221 the proportional width of each column containing a left-aligned
2222 data type. It is specified as a whitespace-separated list of values,
2223 e.g. <literal>'0.2 0.2 0.6'</>. Unspecified output columns
2224 use the last specified value.
2230 <term><literal>title</literal></term>
2233 Sets the table title for any subsequently printed tables. This
2234 can be used to give your output descriptive tags. If no
2235 <replaceable class="parameter">value</replaceable> is given,
2242 <term><literal>tuples_only</literal> (or <literal>t</literal>)</term>
2245 If <replaceable class="parameter">value</replaceable> is specified
2246 it must be either <literal>on</literal> or <literal>off</literal>
2247 which will enable or disable tuples-only mode.
2248 If <replaceable class="parameter">value</replaceable> is omitted the
2249 command toggles between regular and tuples-only output.
2250 Regular output includes extra information such
2251 as column headers, titles, and various footers. In tuples-only
2252 mode, only actual table data is shown.
2260 Illustrations of how these different formats look can be seen in
2261 the <xref linkend="APP-PSQL-examples"
2262 endterm="APP-PSQL-examples-title"> section.
2267 There are various shortcut commands for <command>\pset</command>. See
2268 <command>\a</command>, <command>\C</command>, <command>\H</command>,
2269 <command>\t</command>, <command>\T</command>, and <command>\x</command>.
2275 It is an error to call <command>\pset</command> without any
2276 arguments. In the future this case might show the current status
2277 of all printing options.
2286 <term><literal>\q</literal> or <literal>\quit</literal></term>
2289 Quits the <application>psql</application> program.
2290 In a script file, only execution of that script is terminated.
2297 <term><literal>\qecho <replaceable class="parameter">text</replaceable> [ ... ] </literal></term>
2300 This command is identical to <command>\echo</command> except
2301 that the output will be written to the query output channel, as
2302 set by <command>\o</command>.
2309 <term><literal>\r</literal></term>
2312 Resets (clears) the query buffer.
2319 <term><literal>\s [ <replaceable class="parameter">filename</replaceable> ]</literal></term>
2322 Print or save the command line history to <replaceable
2323 class="parameter">filename</replaceable>. If <replaceable
2324 class="parameter">filename</replaceable> is omitted, the history
2325 is written to the standard output. This option is only available
2326 if <application>psql</application> is configured to use the
2327 <acronym>GNU</acronym> <application>Readline</application> library.
2334 <term><literal>\set [ <replaceable class="parameter">name</replaceable> [ <replaceable class="parameter">value</replaceable> [ ... ] ] ]</literal></term>
2338 Sets the <application>psql</> variable <replaceable
2339 class="parameter">name</replaceable> to <replaceable
2340 class="parameter">value</replaceable>, or if more than one value
2341 is given, to the concatenation of all of them. If only one
2342 argument is given, the variable is set with an empty value. To
2343 unset a variable, use the <command>\unset</command> command.
2346 <para><command>\set</> without any arguments displays the names and values
2347 of all currently-set <application>psql</> variables.
2351 Valid variable names can contain letters, digits, and
2352 underscores. See the section <xref
2353 linkend="APP-PSQL-variables"
2354 endterm="APP-PSQL-variables-title"> below for details.
2355 Variable names are case-sensitive.
2359 Although you are welcome to set any variable to anything you
2360 want, <application>psql</application> treats several variables
2361 as special. They are documented in the section about variables.
2366 This command is unrelated to the <acronym>SQL</acronym>
2367 command <xref linkend="SQL-SET">.
2375 <term><literal>\setenv [ <replaceable class="parameter">name</replaceable> [ <replaceable class="parameter">value</replaceable> ] ]</literal></term>
2379 Sets the environment variable <replaceable
2380 class="parameter">name</replaceable> to <replaceable
2381 class="parameter">value</replaceable>, or if the
2382 <replaceable class="parameter">value</replaceable> is
2383 not supplied, unsets the environment variable. Example:
2385 testdb=> <userinput>\setenv PAGER less</userinput>
2386 testdb=> <userinput>\setenv LESS -imx4F</userinput>
2387 </programlisting></para>
2392 <term><literal>\sf[+] <replaceable class="parameter">function_description</> </literal></term>
2396 This command fetches and shows the definition of the named function,
2397 in the form of a <command>CREATE OR REPLACE FUNCTION</> command.
2398 The definition is printed to the current query output channel,
2399 as set by <command>\o</command>.
2403 The target function can be specified by name alone, or by name
2404 and arguments, for example <literal>foo(integer, text)</>.
2405 The argument types must be given if there is more
2406 than one function of the same name.
2410 If <literal>+</literal> is appended to the command name, then the
2411 output lines are numbered, with the first line of the function body
2419 <term><literal>\t</literal></term>
2422 Toggles the display of output column name headings and row count
2423 footer. This command is equivalent to <literal>\pset
2424 tuples_only</literal> and is provided for convenience.
2431 <term><literal>\T <replaceable class="parameter">table_options</replaceable></literal></term>
2434 Specifies attributes to be placed within the
2435 <sgmltag>table</sgmltag> tag in <acronym>HTML</acronym>
2436 output format. This command is equivalent to <literal>\pset
2437 tableattr <replaceable
2438 class="parameter">table_options</replaceable></literal>.
2445 <term><literal>\timing [ <replaceable class="parameter">on</replaceable> | <replaceable class="parameter">off</replaceable> ]</literal></term>
2448 Without parameter, toggles a display of how long each SQL statement
2449 takes, in milliseconds. With parameter, sets same.
2456 <term><literal>\unset <replaceable class="parameter">name</replaceable></literal></term>
2460 Unsets (deletes) the <application>psql</> variable <replaceable
2461 class="parameter">name</replaceable>.
2468 <term><literal>\w</literal> <replaceable class="parameter">filename</replaceable></term>
2469 <term><literal>\w</literal> <literal>|</><replaceable class="parameter">command</replaceable></term>
2472 Outputs the current query buffer to the file <replaceable
2473 class="parameter">filename</replaceable> or pipes it to the Unix
2474 command <replaceable class="parameter">command</replaceable>.
2481 <term><literal>\x [ <replaceable class="parameter">on</replaceable> | <replaceable class="parameter">off</replaceable> | <replaceable class="parameter">auto</replaceable> ]</literal></term>
2484 Sets or toggles expanded table formatting mode. As such it is equivalent to
2485 <literal>\pset expanded</literal>.
2492 <term><literal>\z [ <link linkend="APP-PSQL-patterns"><replaceable class="parameter">pattern</replaceable></link> ]</literal></term>
2495 Lists tables, views and sequences with their
2496 associated access privileges.
2497 If a <replaceable class="parameter">pattern</replaceable> is
2498 specified, only tables, views and sequences whose names match the
2503 This is an alias for <command>\dp</command> (<quote>display
2504 privileges</quote>).
2511 <term><literal>\! [ <replaceable class="parameter">command</replaceable> ]</literal></term>
2514 Escapes to a separate Unix shell or executes the Unix command
2515 <replaceable class="parameter">command</replaceable>. The
2516 arguments are not further interpreted; the shell will see them
2517 as-is. In particular, the variable substitution rules and
2518 backslash escapes do not apply.
2525 <term><literal>\?</literal></term>
2528 Shows help information about the backslash commands.
2536 <refsect3 id="APP-PSQL-patterns">
2537 <title id="APP-PSQL-patterns-title">Patterns</title>
2540 <primary>patterns</primary>
2541 <secondary>in psql and pg_dump</secondary>
2545 The various <literal>\d</> commands accept a <replaceable
2546 class="parameter">pattern</replaceable> parameter to specify the
2547 object name(s) to be displayed. In the simplest case, a pattern
2548 is just the exact name of the object. The characters within a
2549 pattern are normally folded to lower case, just as in SQL names;
2550 for example, <literal>\dt FOO</> will display the table named
2551 <literal>foo</>. As in SQL names, placing double quotes around
2552 a pattern stops folding to lower case. Should you need to include
2553 an actual double quote character in a pattern, write it as a pair
2554 of double quotes within a double-quote sequence; again this is in
2555 accord with the rules for SQL quoted identifiers. For example,
2556 <literal>\dt "FOO""BAR"</> will display the table named
2557 <literal>FOO"BAR</> (not <literal>foo"bar</>). Unlike the normal
2558 rules for SQL names, you can put double quotes around just part
2559 of a pattern, for instance <literal>\dt FOO"FOO"BAR</> will display
2560 the table named <literal>fooFOObar</>.
2564 Whenever the <replaceable class="parameter">pattern</replaceable> parameter
2565 is omitted completely, the <literal>\d</> commands display all objects
2566 that are visible in the current schema search path — this is
2567 equivalent to using <literal>*</> as the pattern.
2568 (An object is said to be <firstterm>visible</> if its
2569 containing schema is in the search path and no object of the same
2570 kind and name appears earlier in the search path. This is equivalent to the
2571 statement that the object can be referenced by name without explicit
2572 schema qualification.)
2573 To see all objects in the database regardless of visibility,
2574 use <literal>*.*</> as the pattern.
2578 Within a pattern, <literal>*</> matches any sequence of characters
2579 (including no characters) and <literal>?</> matches any single character.
2580 (This notation is comparable to Unix shell file name patterns.)
2581 For example, <literal>\dt int*</> displays tables whose names
2582 begin with <literal>int</>. But within double quotes, <literal>*</>
2583 and <literal>?</> lose these special meanings and are just matched
2588 A pattern that contains a dot (<literal>.</>) is interpreted as a schema
2589 name pattern followed by an object name pattern. For example,
2590 <literal>\dt foo*.*bar*</> displays all tables whose table name
2591 includes <literal>bar</> that are in schemas whose schema name
2592 starts with <literal>foo</>. When no dot appears, then the pattern
2593 matches only objects that are visible in the current schema search path.
2594 Again, a dot within double quotes loses its special meaning and is matched
2599 Advanced users can use regular-expression notations such as character
2600 classes, for example <literal>[0-9]</> to match any digit. All regular
2601 expression special characters work as specified in
2602 <xref linkend="functions-posix-regexp">, except for <literal>.</> which
2603 is taken as a separator as mentioned above, <literal>*</> which is
2604 translated to the regular-expression notation <literal>.*</>,
2605 <literal>?</> which is translated to <literal>.</>, and
2606 <literal>$</> which is matched literally. You can emulate
2607 these pattern characters at need by writing
2608 <literal>?</> for <literal>.</>,
2609 <literal>(<replaceable class="parameter">R</replaceable>+|)</literal> for
2610 <literal><replaceable class="parameter">R</replaceable>*</literal>, or
2611 <literal>(<replaceable class="parameter">R</replaceable>|)</literal> for
2612 <literal><replaceable class="parameter">R</replaceable>?</literal>.
2613 <literal>$</> is not needed as a regular-expression character since
2614 the pattern must match the whole name, unlike the usual
2615 interpretation of regular expressions (in other words, <literal>$</>
2616 is automatically appended to your pattern). Write <literal>*</> at the
2617 beginning and/or end if you don't wish the pattern to be anchored.
2618 Note that within double quotes, all regular expression special characters
2619 lose their special meanings and are matched literally. Also, the regular
2620 expression special characters are matched literally in operator name
2621 patterns (i.e., the argument of <literal>\do</>).
2627 <title>Advanced Features</title>
2629 <refsect3 id="APP-PSQL-variables">
2630 <title id="APP-PSQL-variables-title">Variables</title>
2633 <application>psql</application> provides variable substitution
2634 features similar to common Unix command shells.
2635 Variables are simply name/value pairs, where the value
2636 can be any string of any length. The name must consist of letters
2637 (including non-Latin letters), digits, and underscores.
2641 To set a variable, use the <application>psql</application> meta-command
2642 <command>\set</command>. For example,
2644 testdb=> <userinput>\set foo bar</userinput>
2646 sets the variable <literal>foo</literal> to the value
2647 <literal>bar</literal>. To retrieve the content of the variable, precede
2648 the name with a colon, for example:
2650 testdb=> <userinput>\echo :foo</userinput>
2653 This works in both regular SQL commands and meta-commands; there is
2654 more detail in <xref linkend="APP-PSQL-interpolation"
2655 endterm="APP-PSQL-interpolation-title">, below.
2659 If you call <command>\set</command> without a second argument, the
2660 variable is set, with an empty string as value. To unset (i.e., delete)
2661 a variable, use the command <command>\unset</command>. To show the
2662 values of all variables, call <command>\set</command> without any argument.
2667 The arguments of <command>\set</command> are subject to the same
2668 substitution rules as with other commands. Thus you can construct
2669 interesting references such as <literal>\set :foo
2670 'something'</literal> and get <quote>soft links</quote> or
2671 <quote>variable variables</quote> of <productname>Perl</productname>
2672 or <productname><acronym>PHP</acronym></productname> fame,
2673 respectively. Unfortunately (or fortunately?), there is no way to do
2674 anything useful with these constructs. On the other hand,
2675 <literal>\set bar :foo</literal> is a perfectly valid way to copy a
2681 A number of these variables are treated specially
2682 by <application>psql</application>. They represent certain option
2683 settings that can be changed at run time by altering the value of
2684 the variable, or in some cases represent changeable state of
2685 <application>psql</application>. Although
2686 you can use these variables for other purposes, this is not
2687 recommended, as the program behavior might grow really strange
2688 really quickly. By convention, all specially treated variables' names
2689 consist of all upper-case ASCII letters (and possibly digits and
2690 underscores). To ensure maximum compatibility in the future, avoid
2691 using such variable names for your own purposes. A list of all specially
2692 treated variables follows.
2698 <primary>autocommit</primary>
2699 <secondary>psql</secondary>
2701 <term><varname>AUTOCOMMIT</varname></term>
2704 When <literal>on</> (the default), each SQL command is automatically
2705 committed upon successful completion. To postpone commit in this
2706 mode, you must enter a <command>BEGIN</> or <command>START
2707 TRANSACTION</> SQL command. When <literal>off</> or unset, SQL
2708 commands are not committed until you explicitly issue
2709 <command>COMMIT</> or <command>END</>. The autocommit-off
2710 mode works by issuing an implicit <command>BEGIN</> for you, just
2711 before any command that is not already in a transaction block and
2712 is not itself a <command>BEGIN</> or other transaction-control
2713 command, nor a command that cannot be executed inside a transaction
2714 block (such as <command>VACUUM</>).
2719 In autocommit-off mode, you must explicitly abandon any failed
2720 transaction by entering <command>ABORT</> or <command>ROLLBACK</>.
2721 Also keep in mind that if you exit the session
2722 without committing, your work will be lost.
2728 The autocommit-on mode is <productname>PostgreSQL</>'s traditional
2729 behavior, but autocommit-off is closer to the SQL spec. If you
2730 prefer autocommit-off, you might wish to set it in the system-wide
2731 <filename>psqlrc</filename> file or your
2732 <filename>~/.psqlrc</filename> file.
2739 <term><varname>COMP_KEYWORD_CASE</varname></term>
2742 Determines which letter case to use when completing an SQL key word.
2743 If set to <literal>lower</literal> or <literal>upper</literal>, the
2744 completed word will be in lower or upper case, respectively. If set
2745 to <literal>preserve-lower</literal>
2746 or <literal>preserve-upper</literal> (the default), the completed word
2747 will be in the case of the word already entered, but words being
2748 completed without anything entered will be in lower or upper case,
2755 <term><varname>DBNAME</varname></term>
2758 The name of the database you are currently connected to. This is
2759 set every time you connect to a database (including program
2760 start-up), but can be unset.
2766 <term><varname>ECHO</varname></term>
2769 If set to <literal>all</literal>, all lines
2770 entered from the keyboard or from a script are written to the standard output
2771 before they are parsed or executed. To select this behavior on program
2772 start-up, use the switch <option>-a</option>. If set to
2773 <literal>queries</literal>,
2774 <application>psql</application> merely prints all queries as
2775 they are sent to the server. The switch for this is
2776 <option>-e</option>.
2782 <term><varname>ECHO_HIDDEN</varname></term>
2785 When this variable is set and a backslash command queries the
2786 database, the query is first shown. This way you can study the
2787 <productname>PostgreSQL</productname> internals and provide
2788 similar functionality in your own programs. (To select this behavior
2789 on program start-up, use the switch <option>-E</option>.) If you set
2790 the variable to the value <literal>noexec</literal>, the queries are
2791 just shown but are not actually sent to the server and executed.
2797 <term><varname>ENCODING</varname></term>
2800 The current client character set encoding.
2806 <term><varname>FETCH_COUNT</varname></term>
2809 If this variable is set to an integer value > 0,
2810 the results of <command>SELECT</command> queries are fetched
2811 and displayed in groups of that many rows, rather than the
2812 default behavior of collecting the entire result set before
2813 display. Therefore only a
2814 limited amount of memory is used, regardless of the size of
2815 the result set. Settings of 100 to 1000 are commonly used
2816 when enabling this feature.
2817 Keep in mind that when using this feature, a query might
2818 fail after having already displayed some rows.
2822 Although you can use any output format with this feature,
2823 the default <literal>aligned</> format tends to look bad
2824 because each group of <varname>FETCH_COUNT</varname> rows
2825 will be formatted separately, leading to varying column
2826 widths across the row groups. The other output formats work better.
2833 <term><varname>HISTCONTROL</varname></term>
2836 If this variable is set to <literal>ignorespace</literal>,
2837 lines which begin with a space are not entered into the history
2838 list. If set to a value of <literal>ignoredups</literal>, lines
2839 matching the previous history line are not entered. A value of
2840 <literal>ignoreboth</literal> combines the two options. If
2841 unset, or if set to any other value than those above, all lines
2842 read in interactive mode are saved on the history list.
2846 This feature was shamelessly plagiarized from
2847 <application>Bash</application>.
2854 <term><varname>HISTFILE</varname></term>
2857 The file name that will be used to store the history list. The default
2858 value is <filename>~/.psql_history</filename>. For example, putting:
2860 \set HISTFILE ~/.psql_history- :DBNAME
2862 in <filename>~/.psqlrc</filename> will cause
2863 <application>psql</application> to maintain a separate history for
2868 This feature was shamelessly plagiarized from
2869 <application>Bash</application>.
2876 <term><varname>HISTSIZE</varname></term>
2879 The number of commands to store in the command history. The
2880 default value is 500.
2884 This feature was shamelessly plagiarized from
2885 <application>Bash</application>.
2892 <term><varname>HOST</varname></term>
2895 The database server host you are currently connected to. This is
2896 set every time you connect to a database (including program
2897 start-up), but can be unset.
2903 <term><varname>IGNOREEOF</varname></term>
2906 If unset, sending an <acronym>EOF</> character (usually
2907 <keycombo action="simul"><keycap>Control</><keycap>D</></>)
2908 to an interactive session of <application>psql</application>
2909 will terminate the application. If set to a numeric value,
2910 that many <acronym>EOF</> characters are ignored before the
2911 application terminates. If the variable is set but has no
2912 numeric value, the default is 10.
2916 This feature was shamelessly plagiarized from
2917 <application>Bash</application>.
2924 <term><varname>LASTOID</varname></term>
2927 The value of the last affected OID, as returned from an
2928 <command>INSERT</command> or <command>\lo_import</command>
2929 command. This variable is only guaranteed to be valid until
2930 after the result of the next <acronym>SQL</acronym> command has
2938 <primary>rollback</primary>
2939 <secondary>psql</secondary>
2941 <term><varname>ON_ERROR_ROLLBACK</varname></term>
2944 When <literal>on</>, if a statement in a transaction block
2945 generates an error, the error is ignored and the transaction
2946 continues. When <literal>interactive</>, such errors are only
2947 ignored in interactive sessions, and not when reading script
2948 files. When <literal>off</> (the default), a statement in a
2949 transaction block that generates an error aborts the entire
2950 transaction. The on_error_rollback-on mode works by issuing an
2951 implicit <command>SAVEPOINT</> for you, just before each command
2952 that is in a transaction block, and rolls back to the savepoint
2959 <term><varname>ON_ERROR_STOP</varname></term>
2962 By default, command processing continues after an error. When this
2963 variable is set, it will instead stop immediately. In interactive mode,
2964 <application>psql</application> will return to the command prompt;
2965 otherwise, <application>psql</application> will exit, returning
2966 error code 3 to distinguish this case from fatal error
2967 conditions, which are reported using error code 1. In either case,
2968 any currently running scripts (the top-level script, if any, and any
2969 other scripts which it may have in invoked) will be terminated
2970 immediately. If the top-level command string contained multiple SQL
2971 commands, processing will stop with the current command.
2977 <term><varname>PORT</varname></term>
2980 The database server port to which you are currently connected.
2981 This is set every time you connect to a database (including
2982 program start-up), but can be unset.
2988 <term><varname>PROMPT1</varname></term>
2989 <term><varname>PROMPT2</varname></term>
2990 <term><varname>PROMPT3</varname></term>
2993 These specify what the prompts <application>psql</application>
2994 issues should look like. See <xref
2995 linkend="APP-PSQL-prompting"
2996 endterm="APP-PSQL-prompting-title"> below.
3002 <term><varname>QUIET</varname></term>
3005 This variable is equivalent to the command line option
3006 <option>-q</option>. It is probably not too useful in
3013 <term><varname>SINGLELINE</varname></term>
3016 This variable is equivalent to the command line option
3017 <option>-S</option>.
3023 <term><varname>SINGLESTEP</varname></term>
3026 This variable is equivalent to the command line option
3027 <option>-s</option>.
3033 <term><varname>USER</varname></term>
3036 The database user you are currently connected as. This is set
3037 every time you connect to a database (including program
3038 start-up), but can be unset.
3044 <term><varname>VERBOSITY</varname></term>
3047 This variable can be set to the values <literal>default</>,
3048 <literal>verbose</>, or <literal>terse</> to control the verbosity
3058 <refsect3 id="APP-PSQL-interpolation">
3059 <title id="APP-PSQL-interpolation-title"><acronym>SQL</acronym> Interpolation</title>
3062 A key feature of <application>psql</application>
3063 variables is that you can substitute (<quote>interpolate</quote>)
3064 them into regular <acronym>SQL</acronym> statements, as well as the
3065 arguments of meta-commands. Furthermore,
3066 <application>psql</application> provides facilities for
3067 ensuring that variable values used as SQL literals and identifiers are
3068 properly quoted. The syntax for interpolating a value without
3069 any quoting is to prepend the variable name with a colon
3070 (<literal>:</literal>). For example,
3072 testdb=> <userinput>\set foo 'my_table'</userinput>
3073 testdb=> <userinput>SELECT * FROM :foo;</userinput>
3075 would query the table <literal>my_table</literal>. Note that this
3076 may be unsafe: the value of the variable is copied literally, so it can
3077 contain unbalanced quotes, or even backslash commands. You must make sure
3078 that it makes sense where you put it.
3082 When a value is to be used as an SQL literal or identifier, it is
3083 safest to arrange for it to be quoted. To quote the value of
3084 a variable as an SQL literal, write a colon followed by the variable
3085 name in single quotes. To quote the value as an SQL identifier, write
3086 a colon followed by the variable name in double quotes.
3087 These constructs deal correctly with quotes and other special
3088 characters embedded within the variable value.
3089 The previous example would be more safely written this way:
3091 testdb=> <userinput>\set foo 'my_table'</userinput>
3092 testdb=> <userinput>SELECT * FROM :"foo";</userinput>
3097 Variable interpolation will not be performed within quoted
3098 <acronym>SQL</acronym> literals and identifiers. Therefore, a
3099 construction such as <literal>':foo'</> doesn't work to produce a quoted
3100 literal from a variable's value (and it would be unsafe if it did work,
3101 since it wouldn't correctly handle quotes embedded in the value).
3105 One example use of this mechanism is to
3106 copy the contents of a file into a table column.
3107 First load the file into a variable and then interpolate the variable's
3108 value as a quoted string:
3110 testdb=> <userinput>\set content `cat my_file.txt`</userinput>
3111 testdb=> <userinput>INSERT INTO my_table VALUES (:'content');</userinput>
3113 (Note that this still won't work if <filename>my_file.txt</filename> contains NUL bytes.
3114 <application>psql</application> does not support embedded NUL bytes in variable values.)
3118 Since colons can legally appear in SQL commands, an apparent attempt
3119 at interpolation (that is, <literal>:name</literal>,
3120 <literal>:'name'</literal>, or <literal>:"name"</literal>) is not
3121 replaced unless the named variable is currently set. In any case, you
3122 can escape a colon with a backslash to protect it from substitution.
3126 The colon syntax for variables is standard <acronym>SQL</acronym> for
3127 embedded query languages, such as <application>ECPG</application>.
3128 The colon syntaxes for array slices and type casts are
3129 <productname>PostgreSQL</productname> extensions, which can sometimes
3130 conflict with the standard usage. The colon-quote syntax for escaping a
3131 variable's value as an SQL literal or identifier is a
3132 <application>psql</application> extension.
3137 <refsect3 id="APP-PSQL-prompting">
3138 <title id="APP-PSQL-prompting-title">Prompting</title>
3141 The prompts <application>psql</application> issues can be customized
3142 to your preference. The three variables <varname>PROMPT1</varname>,
3143 <varname>PROMPT2</varname>, and <varname>PROMPT3</varname> contain strings
3144 and special escape sequences that describe the appearance of the
3145 prompt. Prompt 1 is the normal prompt that is issued when
3146 <application>psql</application> requests a new command. Prompt 2 is
3147 issued when more input is expected during command input because the
3148 command was not terminated with a semicolon or a quote was not closed.
3149 Prompt 3 is issued when you run an <acronym>SQL</acronym>
3150 <command>COPY</command> command and you are expected to type in the
3151 row values on the terminal.
3155 The value of the selected prompt variable is printed literally,
3156 except where a percent sign (<literal>%</literal>) is encountered.
3157 Depending on the next character, certain other text is substituted
3158 instead. Defined substitutions are:
3162 <term><literal>%M</literal></term>
3165 The full host name (with domain name) of the database server,
3166 or <literal>[local]</literal> if the connection is over a Unix
3168 <literal>[local:<replaceable>/dir/name</replaceable>]</literal>,
3169 if the Unix domain socket is not at the compiled in default
3176 <term><literal>%m</literal></term>
3179 The host name of the database server, truncated at the
3180 first dot, or <literal>[local]</literal> if the connection is
3181 over a Unix domain socket.
3187 <term><literal>%></literal></term>
3188 <listitem><para>The port number at which the database server is listening.</para></listitem>
3192 <term><literal>%n</literal></term>
3195 The database session user name. (The expansion of this
3196 value might change during a database session as the result
3197 of the command <command>SET SESSION
3198 AUTHORIZATION</command>.)
3204 <term><literal>%/</literal></term>
3205 <listitem><para>The name of the current database.</para></listitem>
3209 <term><literal>%~</literal></term>
3210 <listitem><para>Like <literal>%/</literal>, but the output is <literal>~</literal>
3211 (tilde) if the database is your default database.</para></listitem>
3215 <term><literal>%#</literal></term>
3218 If the session user is a database superuser, then a
3219 <literal>#</literal>, otherwise a <literal>></literal>.
3220 (The expansion of this value might change during a database
3221 session as the result of the command <command>SET SESSION
3222 AUTHORIZATION</command>.)
3228 <term><literal>%R</literal></term>
3231 In prompt 1 normally <literal>=</literal>, but <literal>^</literal> if
3232 in single-line mode, and <literal>!</literal> if the session is
3233 disconnected from the database (which can happen if
3234 <command>\connect</command> fails). In prompt 2 the sequence is
3235 replaced by <literal>-</literal>, <literal>*</literal>, a single quote,
3236 a double quote, or a dollar sign, depending on whether
3237 <application>psql</application> expects more input because the
3238 command wasn't terminated yet, because you are inside a
3239 <literal>/* ... */</literal> comment, or because you are inside
3240 a quoted or dollar-escaped string. In prompt 3 the sequence doesn't
3247 <term><literal>%x</literal></term>
3250 Transaction status: an empty string when not in a transaction
3251 block, or <literal>*</> when in a transaction block, or
3252 <literal>!</> when in a failed transaction block, or <literal>?</>
3253 when the transaction state is indeterminate (for example, because
3254 there is no connection).
3260 <term><literal>%</literal><replaceable class="parameter">digits</replaceable></term>
3263 The character with the indicated octal code is substituted.
3269 <term><literal>%:</literal><replaceable class="parameter">name</replaceable><literal>:</literal></term>
3272 The value of the <application>psql</application> variable
3273 <replaceable class="parameter">name</replaceable>. See the
3274 section <xref linkend="APP-PSQL-variables"
3275 endterm="APP-PSQL-variables-title"> for details.
3281 <term><literal>%`</literal><replaceable class="parameter">command</replaceable><literal>`</literal></term>
3284 The output of <replaceable
3285 class="parameter">command</replaceable>, similar to ordinary
3286 <quote>back-tick</quote> substitution.
3292 <term><literal>%[</literal> ... <literal>%]</literal></term>
3295 Prompts can contain terminal control characters which, for
3296 example, change the color, background, or style of the prompt
3297 text, or change the title of the terminal window. In order for
3298 the line editing features of <application>Readline</application> to work properly, these
3299 non-printing control characters must be designated as invisible
3300 by surrounding them with <literal>%[</literal> and
3301 <literal>%]</literal>. Multiple pairs of these can occur within
3302 the prompt. For example:
3304 testdb=> \set PROMPT1 '%[%033[1;33;40m%]%n@%/%R%[%033[0m%]%# '
3306 results in a boldfaced (<literal>1;</literal>) yellow-on-black
3307 (<literal>33;40</literal>) prompt on VT100-compatible, color-capable
3315 To insert a percent sign into your prompt, write
3316 <literal>%%</literal>. The default prompts are
3317 <literal>'%/%R%# '</literal> for prompts 1 and 2, and
3318 <literal>'>> '</literal> for prompt 3.
3323 This feature was shamelessly plagiarized from
3324 <application>tcsh</application>.
3331 <title>Command-Line Editing</title>
3334 <application>psql</application> supports the <application>Readline</application>
3335 library for convenient line editing and retrieval. The command
3336 history is automatically saved when <application>psql</application>
3337 exits and is reloaded when
3338 <application>psql</application> starts up. Tab-completion is also
3339 supported, although the completion logic makes no claim to be an
3340 <acronym>SQL</acronym> parser. The queries generated by tab-completion
3341 can also interfere with other SQL commands, e.g. <literal>SET
3342 TRANSACTION ISOLATION LEVEL</>.
3343 If for some reason you do not like the tab completion, you
3344 can turn it off by putting this in a file named
3345 <filename>.inputrc</filename> in your home directory:
3348 set disable-completion on
3351 (This is not a <application>psql</application> but a
3352 <application>Readline</application> feature. Read its documentation
3353 for further details.)
3360 <refsect1 id="app-psql-environment">
3361 <title id="app-psql-environment-title">Environment</title>
3366 <term><envar>COLUMNS</envar></term>
3370 If <literal>\pset columns</> is zero, controls the
3371 width for the <literal>wrapped</> format and width for determining
3372 if wide output requires the pager or should be switched to the
3373 vertical format in expanded auto mode.
3379 <term><envar>PAGER</envar></term>
3383 If the query results do not fit on the screen, they are piped
3384 through this command. Typical values are
3385 <literal>more</literal> or <literal>less</literal>. The default
3386 is platform-dependent. The use of the pager can be disabled by
3387 using the <command>\pset</command> command.
3393 <term><envar>PGDATABASE</envar></term>
3394 <term><envar>PGHOST</envar></term>
3395 <term><envar>PGPORT</envar></term>
3396 <term><envar>PGUSER</envar></term>
3400 Default connection parameters (see <xref linkend="libpq-envars">).
3406 <term><envar>PSQL_EDITOR</envar></term>
3407 <term><envar>EDITOR</envar></term>
3408 <term><envar>VISUAL</envar></term>
3412 Editor used by the <command>\e</command> and
3413 <command>\ef</command> commands. The variables are examined in
3414 the order listed; the first that is set is used.
3418 The built-in default editors are <filename>vi</filename> on Unix
3419 systems and <filename>notepad.exe</filename> on Windows systems.
3425 <term><envar>PSQL_EDITOR_LINENUMBER_ARG</envar></term>
3429 When <command>\e</command> or <command>\ef</command> is used
3430 with a line number argument, this variable specifies the
3431 command-line argument used to pass the starting line number to
3432 the user's editor. For editors such as <productname>Emacs</> or
3433 <productname>vi</>, this is a plus sign. Include a trailing
3434 space in the value of the variable if there needs to be space
3435 between the option name and the line number. Examples:
3437 PSQL_EDITOR_LINENUMBER_ARG='+'
3438 PSQL_EDITOR_LINENUMBER_ARG='--line '
3443 The default is <literal>+</literal> on Unix systems
3444 (corresponding to the default editor <filename>vi</filename>,
3445 and useful for many other common editors); but there is no
3446 default on Windows systems.
3452 <term><envar>PSQL_HISTORY</envar></term>
3456 Alternative location for the command history file. Tilde (<literal>~</literal>) expansion is performed.
3462 <term><envar>PSQLRC</envar></term>
3466 Alternative location of the user's <filename>.psqlrc</filename> file. Tilde (<literal>~</literal>) expansion is performed.
3472 <term><envar>SHELL</envar></term>
3476 Command executed by the <command>\!</command> command.
3482 <term><envar>TMPDIR</envar></term>
3486 Directory for storing temporary files. The default is
3487 <filename>/tmp</filename>.
3494 This utility, like most other <productname>PostgreSQL</> utilities,
3495 also uses the environment variables supported by <application>libpq</>
3496 (see <xref linkend="libpq-envars">).
3503 <title>Files</title>
3508 Unless it is passed an <option>-X</option>
3509 or <option>-c</option> option,
3510 <application>psql</application> attempts to
3511 read and execute commands from the system-wide
3512 <filename>psqlrc</filename> file and the user's
3513 <filename>~/.psqlrc</filename> file before starting up.
3514 (On Windows, the user's startup file is named
3515 <filename>%APPDATA%\postgresql\psqlrc.conf</filename>.)
3516 See <filename><replaceable>PREFIX</>/share/psqlrc.sample</>
3517 for information on setting up the system-wide file. It could be used
3518 to set up the client or the server to taste (using the <command>\set
3519 </command> and <command>SET</command> commands).
3522 The location of the user's <filename>~/.psqlrc</filename> file can
3523 also be set explicitly via the <envar>PSQLRC</envar> environment
3530 Both the system-wide <filename>psqlrc</filename> file and the user's
3531 <filename>~/.psqlrc</filename> file can be made <application>psql</application>-version-specific
3532 by appending a dash and the <productname>PostgreSQL</productname>
3533 major or minor <application>psql</application> release number,
3534 for example <filename>~/.psqlrc-9.2</filename> or
3535 <filename>~/.psqlrc-9.2.5</filename>. The most specific
3536 version-matching file will be read in preference to a
3537 non-version-specific file.
3543 The command-line history is stored in the file
3544 <filename>~/.psql_history</filename>, or
3545 <filename>%APPDATA%\postgresql\psql_history</filename> on Windows.
3548 The location of the history file can
3549 also be set explicitly via the <envar>PSQL_HISTORY</envar> environment
3558 <title>Notes</title>
3563 In an earlier life <application>psql</application> allowed the
3564 first argument of a single-letter backslash command to start
3565 directly after the command, without intervening whitespace.
3566 As of <productname>PostgreSQL</productname> 8.4 this is no
3572 <para><application>psql</application> works best with servers of the same
3573 or an older major version. Backslash commands are particularly likely
3574 to fail if the server is of a newer version than <application>psql</>
3575 itself. However, backslash commands of the <literal>\d</> family should
3576 work with servers of versions back to 7.4, though not necessarily with
3577 servers newer than <application>psql</> itself. The general
3578 functionality of running SQL commands and displaying query results
3579 should also work with servers of a newer major version, but this cannot
3580 be guaranteed in all cases.
3583 If you want to use <application>psql</application> to connect to several
3584 servers of different major versions, it is recommended that you use the
3585 newest version of <application>psql</application>. Alternatively, you
3586 can keep a copy of <application>psql</application> from each major
3587 version around and be sure to use the version that matches the
3588 respective server. But in practice, this additional complication should
3598 <title>Notes for Windows Users</title>
3601 <application>psql</application> is built as a <quote>console
3602 application</>. Since the Windows console windows use a different
3603 encoding than the rest of the system, you must take special care
3604 when using 8-bit characters within <application>psql</application>.
3605 If <application>psql</application> detects a problematic
3606 console code page, it will warn you at startup. To change the
3607 console code page, two things are necessary:
3612 Set the code page by entering <userinput>cmd.exe /c chcp
3613 1252</userinput>. (1252 is a code page that is appropriate for
3614 German; replace it with your value.) If you are using Cygwin,
3615 you can put this command in <filename>/etc/profile</filename>.
3621 Set the console font to <literal>Lucida Console</>, because the
3622 raster font does not work with the ANSI code page.
3625 </itemizedlist></para>
3630 <refsect1 id="APP-PSQL-examples">
3631 <title id="APP-PSQL-examples-title">Examples</title>
3634 The first example shows how to spread a command over several lines of
3635 input. Notice the changing prompt:
3637 testdb=> <userinput>CREATE TABLE my_table (</userinput>
3638 testdb(> <userinput> first integer not null default 0,</userinput>
3639 testdb(> <userinput> second text)</userinput>
3640 testdb-> <userinput>;</userinput>
3643 Now look at the table definition again:
3645 testdb=> <userinput>\d my_table</userinput>
3647 Attribute | Type | Modifier
3648 -----------+---------+--------------------
3649 first | integer | not null default 0
3653 Now we change the prompt to something more interesting:
3655 testdb=> <userinput>\set PROMPT1 '%n@%m %~%R%# '</userinput>
3656 peter@localhost testdb=>
3658 Let's assume you have filled the table with data and want to take a
3661 peter@localhost testdb=> SELECT * FROM my_table;
3671 You can display tables in different ways by using the
3672 <command>\pset</command> command:
3674 peter@localhost testdb=> <userinput>\pset border 2</userinput>
3676 peter@localhost testdb=> <userinput>SELECT * FROM my_table;</userinput>
3687 peter@localhost testdb=> <userinput>\pset border 0</userinput>
3689 peter@localhost testdb=> <userinput>SELECT * FROM my_table;</userinput>
3698 peter@localhost testdb=> <userinput>\pset border 1</userinput>
3700 peter@localhost testdb=> <userinput>\pset format unaligned</userinput>
3701 Output format is unaligned.
3702 peter@localhost testdb=> <userinput>\pset fieldsep ","</userinput>
3703 Field separator is ",".
3704 peter@localhost testdb=> <userinput>\pset tuples_only</userinput>
3705 Showing only tuples.
3706 peter@localhost testdb=> <userinput>SELECT second, first FROM my_table;</userinput>
3712 Alternatively, use the short commands:
3714 peter@localhost testdb=> <userinput>\a \t \x</userinput>
3715 Output format is aligned.
3717 Expanded display is on.
3718 peter@localhost testdb=> <userinput>SELECT * FROM my_table;</userinput>
3731 </programlisting></para>