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PSQL(1) 			  PostgreSQL 9.2.7 Documentation			  PSQL(1)

NAME
       psql - PostgreSQL interactive terminal

SYNOPSIS
       psql [option...] [dbname [username]]

DESCRIPTION
       psql is a terminal-based front-end to PostgreSQL. It enables you to type in queries
       interactively, issue them to PostgreSQL, and see the query results. Alternatively, input
       can be from a file. In addition, it provides a number of meta-commands and various
       shell-like features to facilitate writing scripts and automating a wide variety of tasks.

OPTIONS
       -a, --echo-all
	   Print all input lines to standard output as they are read. This is more useful for
	   script processing than interactive mode. This is equivalent to setting the variable
	   ECHO to all.

       -A, --no-align
	   Switches to unaligned output mode. (The default output mode is otherwise aligned.)

       -c command, --command=command
	   Specifies that psql is to execute one command string, command, and then exit. This is
	   useful in shell scripts. Start-up files (psqlrc and ~/.psqlrc) are ignored with this
	   option.

	   command must be either a command string that is completely parsable by the server
	   (i.e., it contains no psql-specific features), or a single backslash command. Thus you
	   cannot mix SQL and psql meta-commands with this option. To achieve that, you could
	   pipe the string into psql, for example: echo '\x \\ SELECT * FROM foo;' | psql. (\\ is
	   the separator meta-command.)

	   If the command string contains multiple SQL commands, they are processed in a single
	   transaction, unless there are explicit BEGIN/COMMIT commands included in the string to
	   divide it into multiple transactions. This is different from the behavior when the
	   same string is fed to psql's standard input. Also, only the result of the last SQL
	   command is returned.

	   Because of these legacy behaviors, putting more than one command in the -c string
	   often has unexpected results. It's better to feed multiple commands to psql's standard
	   input, either using echo as illustrated above, or via a shell here-document, for
	   example:

	       psql <<EOF
	       \x
	       SELECT * FROM foo;
	       EOF

       -d dbname, --dbname=dbname
	   Specifies the name of the database to connect to. This is equivalent to specifying
	   dbname as the first non-option argument on the command line.

	   If this parameter contains an = sign or starts with a valid URI prefix (postgresql://
	   or postgres://), it is treated as a conninfo string. See Section 31.1, "Database
	   Connection Control Functions", in the documentation for more information.

       -e, --echo-queries
	   Copy all SQL commands sent to the server to standard output as well. This is
	   equivalent to setting the variable ECHO to queries.

       -E, --echo-hidden
	   Echo the actual queries generated by \d and other backslash commands. You can use this
	   to study psql's internal operations. This is equivalent to setting the variable
	   ECHO_HIDDEN from within psql.

       -f filename, --file=filename
	   Use the file filename as the source of commands instead of reading commands
	   interactively. After the file is processed, psql terminates. This is in many ways
	   equivalent to the meta-command \i.

	   If filename is - (hyphen), then standard input is read.

	   Using this option is subtly different from writing psql < filename. In general, both
	   will do what you expect, but using -f enables some nice features such as error
	   messages with line numbers. There is also a slight chance that using this option will
	   reduce the start-up overhead. On the other hand, the variant using the shell's input
	   redirection is (in theory) guaranteed to yield exactly the same output you would have
	   received had you entered everything by hand.

       -F separator, --field-separator=separator
	   Use separator as the field separator for unaligned output. This is equivalent to \pset
	   fieldsep or \f.

       -h hostname, --host=hostname
	   Specifies the host name of the machine on which the server is running. If the value
	   begins with a slash, it is used as the directory for the Unix-domain socket.

       -H, --html
	   Turn on HTML tabular output. This is equivalent to \pset format html or the \H
	   command.

       -l, --list
	   List all available databases, then exit. Other non-connection options are ignored.
	   This is similar to the meta-command \list.

       -L filename, --log-file=filename
	   Write all query output into file filename, in addition to the normal output
	   destination.

       -n, --no-readline
	   Do not use readline for line editing and do not use the history. This can be useful to
	   turn off tab expansion when cutting and pasting.

       -o filename, --output=filename
	   Put all query output into file filename. This is equivalent to the command \o.

       -p port, --port=port
	   Specifies the TCP port or the local Unix-domain socket file extension on which the
	   server is listening for connections. Defaults to the value of the PGPORT environment
	   variable or, if not set, to the port specified at compile time, usually 5432.

       -P assignment, --pset=assignment
	   Specifies printing options, in the style of \pset. Note that here you have to separate
	   name and value with an equal sign instead of a space. For example, to set the output
	   format to LaTeX, you could write -P format=latex.

       -q, --quiet
	   Specifies that psql should do its work quietly. By default, it prints welcome messages
	   and various informational output. If this option is used, none of this happens. This
	   is useful with the -c option. Within psql you can also set the QUIET variable to
	   achieve the same effect.

       -R separator, --record-separator=separator
	   Use separator as the record separator for unaligned output. This is equivalent to the
	   \pset recordsep command.

       -s, --single-step
	   Run in single-step mode. That means the user is prompted before each command is sent
	   to the server, with the option to cancel execution as well. Use this to debug scripts.

       -S, --single-line
	   Runs in single-line mode where a newline terminates an SQL command, as a semicolon
	   does.

	       Note
	       This mode is provided for those who insist on it, but you are not necessarily
	       encouraged to use it. In particular, if you mix SQL and meta-commands on a line
	       the order of execution might not always be clear to the inexperienced user.

       -t, --tuples-only
	   Turn off printing of column names and result row count footers, etc. This is
	   equivalent to the \t command.

       -T table_options, --table-attr=table_options
	   Specifies options to be placed within the HTML table tag. See \pset for details.

       -U username, --username=username
	   Connect to the database as the user username instead of the default. (You must have
	   permission to do so, of course.)

       -v assignment, --set=assignment, --variable=assignment
	   Perform a variable assignment, like the \set meta-command. Note that you must separate
	   name and value, if any, by an equal sign on the command line. To unset a variable,
	   leave off the equal sign. To set a variable with an empty value, use the equal sign
	   but leave off the value. These assignments are done during a very early stage of
	   start-up, so variables reserved for internal purposes might get overwritten later.

       -V, --version
	   Print the psql version and exit.

       -w, --no-password
	   Never issue a password prompt. If the server requires password authentication and a
	   password is not available by other means such as a .pgpass file, the connection
	   attempt will fail. This option can be useful in batch jobs and scripts where no user
	   is present to enter a password.

	   Note that this option will remain set for the entire session, and so it affects uses
	   of the meta-command \connect as well as the initial connection attempt.

       -W, --password
	   Force psql to prompt for a password before connecting to a database.

	   This option is never essential, since psql will automatically prompt for a password if
	   the server demands password authentication. However, psql will waste a connection
	   attempt finding out that the server wants a password. In some cases it is worth typing
	   -W to avoid the extra connection attempt.

	   Note that this option will remain set for the entire session, and so it affects uses
	   of the meta-command \connect as well as the initial connection attempt.

       -x, --expanded
	   Turn on the expanded table formatting mode. This is equivalent to the \x command.

       -X,, --no-psqlrc
	   Do not read the start-up file (neither the system-wide psqlrc file nor the user's
	   ~/.psqlrc file).

       -z, --field-separator-zero
	   Set the field separator for unaligned output to a zero byte.

       -0, --record-separator-zero
	   Set the record separator for unaligned output to a zero byte. This is useful for
	   interfacing, for example, with xargs -0.

       -1, --single-transaction
	   When psql executes a script with the -f option, adding this option wraps BEGIN/COMMIT
	   around the script to execute it as a single transaction. This ensures that either all
	   the commands complete successfully, or no changes are applied.

	   If the script itself uses BEGIN, COMMIT, or ROLLBACK, this option will not have the
	   desired effects. Also, if the script contains any command that cannot be executed
	   inside a transaction block, specifying this option will cause that command (and hence
	   the whole transaction) to fail.

       -?, --help
	   Show help about psql command line arguments, and exit.

EXIT STATUS
       psql returns 0 to the shell if it finished normally, 1 if a fatal error of its own occurs
       (e.g. out of memory, file not found), 2 if the connection to the server went bad and the
       session was not interactive, and 3 if an error occurred in a script and the variable
       ON_ERROR_STOP was set.

USAGE
   Connecting to a Database
       psql is a regular PostgreSQL client application. In order to connect to a database you
       need to know the name of your target database, the host name and port number of the
       server, and what user name you want to connect as.  psql can be told about those
       parameters via command line options, namely -d, -h, -p, and -U respectively. If an
       argument is found that does not belong to any option it will be interpreted as the
       database name (or the user name, if the database name is already given). Not all of these
       options are required; there are useful defaults. If you omit the host name, psql will
       connect via a Unix-domain socket to a server on the local host, or via TCP/IP to localhost
       on machines that don't have Unix-domain sockets. The default port number is determined at
       compile time. Since the database server uses the same default, you will not have to
       specify the port in most cases. The default user name is your Unix user name, as is the
       default database name. Note that you cannot just connect to any database under any user
       name. Your database administrator should have informed you about your access rights.

       When the defaults aren't quite right, you can save yourself some typing by setting the
       environment variables PGDATABASE, PGHOST, PGPORT and/or PGUSER to appropriate values. (For
       additional environment variables, see Section 31.14, "Environment Variables", in the
       documentation.) It is also convenient to have a ~/.pgpass file to avoid regularly having
       to type in passwords. See Section 31.15, "The Password File", in the documentation for
       more information.

       An alternative way to specify connection parameters is in a conninfo string or a URI,
       which is used instead of a database name. This mechanism give you very wide control over
       the connection. For example:

	   $ psql "service=myservice sslmode=require"
	   $ psql postgresql://dbmaster:5433/mydb?sslmode=require

       This way you can also use LDAP for connection parameter lookup as described in Section
       31.17, "LDAP Lookup of Connection Parameters", in the documentation. See Section 31.1,
       "Database Connection Control Functions", in the documentation for more information on all
       the available connection options.

       If the connection could not be made for any reason (e.g., insufficient privileges, server
       is not running on the targeted host, etc.), psql will return an error and terminate.

       If at least one of standard input or standard output are a terminal, then psql sets the
       client encoding to "auto", which will detect the appropriate client encoding from the
       locale settings (LC_CTYPE environment variable on Unix systems). If this doesn't work out
       as expected, the client encoding can be overridden using the environment variable
       PGCLIENTENCODING.

   Entering SQL Commands
       In normal operation, psql provides a prompt with the name of the database to which psql is
       currently connected, followed by the string =>. For example:

	   $ psql testdb
	   psql (9.2.7)
	   Type "help" for help.

	   testdb=>

       At the prompt, the user can type in SQL commands. Ordinarily, input lines are sent to the
       server when a command-terminating semicolon is reached. An end of line does not terminate
       a command. Thus commands can be spread over several lines for clarity. If the command was
       sent and executed without error, the results of the command are displayed on the screen.

       Whenever a command is executed, psql also polls for asynchronous notification events
       generated by LISTEN(7) and NOTIFY(7).

   Meta-Commands
       Anything you enter in psql that begins with an unquoted backslash is a psql meta-command
       that is processed by psql itself. These commands make psql more useful for administration
       or scripting. Meta-commands are often called slash or backslash commands.

       The format of a psql command is the backslash, followed immediately by a command verb,
       then any arguments. The arguments are separated from the command verb and each other by
       any number of whitespace characters.

       To include whitespace in an argument you can quote it with single quotes. To include a
       single quote in an argument, write two single quotes within single-quoted text. Anything
       contained in single quotes is furthermore subject to C-like substitutions for \n (new
       line), \t (tab), \b (backspace), \r (carriage return), \f (form feed), \digits (octal),
       and \xdigits (hexadecimal). A backslash preceding any other character within single-quoted
       text quotes that single character, whatever it is.

       Within an argument, text that is enclosed in backquotes (`) is taken as a command line
       that is passed to the shell. The output of the command (with any trailing newline removed)
       replaces the backquoted text.

       If an unquoted colon (:) followed by a psql variable name appears within an argument, it
       is replaced by the variable's value, as described in SQL Interpolation.

       Some commands take an SQL identifier (such as a table name) as argument. These arguments
       follow the syntax rules of SQL: Unquoted letters are forced to lowercase, while double
       quotes (") protect letters from case conversion and allow incorporation of whitespace into
       the identifier. Within double quotes, paired double quotes reduce to a single double quote
       in the resulting name. For example, FOO"BAR"BAZ is interpreted as fooBARbaz, and "A
       weird"" name" becomes A weird" name.

       Parsing for arguments stops at the end of the line, or when another unquoted backslash is
       found. An unquoted backslash is taken as the beginning of a new meta-command. The special
       sequence \\ (two backslashes) marks the end of arguments and continues parsing SQL
       commands, if any. That way SQL and psql commands can be freely mixed on a line. But in any
       case, the arguments of a meta-command cannot continue beyond the end of the line.

       The following meta-commands are defined:

       \a
	   If the current table output format is unaligned, it is switched to aligned. If it is
	   not unaligned, it is set to unaligned. This command is kept for backwards
	   compatibility. See \pset for a more general solution.

       \c or \connect [ dbname [ username ] [ host ] [ port ] ]
	   Establishes a new connection to a PostgreSQL server. If the new connection is
	   successfully made, the previous connection is closed. If any of dbname, username, host
	   or port are omitted or specified as -, the value of that parameter from the previous
	   connection is used. If there is no previous connection, the libpq default for the
	   parameter's value is used.

	   If the connection attempt failed (wrong user name, access denied, etc.), the previous
	   connection will only be kept if psql is in interactive mode. When executing a
	   non-interactive script, processing will immediately stop with an error. This
	   distinction was chosen as a user convenience against typos on the one hand, and a
	   safety mechanism that scripts are not accidentally acting on the wrong database on the
	   other hand.

       \C [ title ]
	   Sets the title of any tables being printed as the result of a query or unset any such
	   title. This command is equivalent to \pset title title. (The name of this command
	   derives from "caption", as it was previously only used to set the caption in an HTML
	   table.)

       \cd [ directory ]
	   Changes the current working directory to directory. Without argument, changes to the
	   current user's home directory.

	       Tip
	       To print your current working directory, use \! pwd.

       \conninfo
	   Outputs information about the current database connection.

       \copy { table [ ( column_list ) ] | ( query ) } { from | to } { filename | stdin | stdout
       | pstdin | pstdout } [ with ] [ binary ] [ oids ] [ delimiter [ as ] 'character' ] [ null
       [ as ] 'string' ] [ csv [ header ] [ quote [ as ] 'character' ] [ escape [ as ]
       'character' ] [ force quote column_list | * ] [ force not null column_list ] ]
	   Performs a frontend (client) copy. This is an operation that runs an SQL COPY(7)
	   command, but instead of the server reading or writing the specified file, psql reads
	   or writes the file and routes the data between the server and the local file system.
	   This means that file accessibility and privileges are those of the local user, not the
	   server, and no SQL superuser privileges are required.

	   The syntax of the command is similar to that of the SQL COPY(7) command. Note that,
	   because of this, special parsing rules apply to the \copy command. In particular, the
	   variable substitution rules and backslash escapes do not apply.

	   \copy ... from stdin | to stdout reads/writes based on the command input and output
	   respectively. All rows are read from the same source that issued the command,
	   continuing until \.	is read or the stream reaches EOF. Output is sent to the same
	   place as command output. To read/write from psql's standard input or output, use
	   pstdin or pstdout. This option is useful for populating tables in-line within a SQL
	   script file.

	       Tip
	       This operation is not as efficient as the SQL COPY command because all data must
	       pass through the client/server connection. For large amounts of data the SQL
	       command might be preferable.

       \copyright
	   Shows the copyright and distribution terms of PostgreSQL.

       \d[S+] [ pattern ]
	   For each relation (table, view, index, sequence, or foreign table) or composite type
	   matching the pattern, show all columns, their types, the tablespace (if not the
	   default) and any special attributes such as NOT NULL or defaults. Associated indexes,
	   constraints, rules, and triggers are also shown. For foreign tables, the associated
	   foreign server is shown as well. ("Matching the pattern" is defined in Patterns
	   below.)

	   For some types of relation, \d shows additional information for each column: column
	   values for sequences, indexed expression for indexes and foreign data wrapper options
	   for foreign tables.

	   The command form \d+ is identical, except that more information is displayed: any
	   comments associated with the columns of the table are shown, as is the presence of
	   OIDs in the table, the view definition if the relation is a view.

	   By default, only user-created objects are shown; supply a pattern or the S modifier to
	   include system objects.

	       Note
	       If \d is used without a pattern argument, it is equivalent to \dtvsE which will
	       show a list of all visible tables, views, sequences and foreign tables. This is
	       purely a convenience measure.

       \da[S] [ pattern ]
	   Lists aggregate functions, together with their return type and the data types they
	   operate on. If pattern is specified, only aggregates whose names match the pattern are
	   shown. By default, only user-created objects are shown; supply a pattern or the S
	   modifier to include system objects.

       \db[+] [ pattern ]
	   Lists tablespaces. If pattern is specified, only tablespaces whose names match the
	   pattern are shown. If + is appended to the command name, each object is listed with
	   its associated permissions.

       \dc[S+] [ pattern ]
	   Lists conversions between character-set encodings. If pattern is specified, only
	   conversions whose names match the pattern are listed. By default, only user-created
	   objects are shown; supply a pattern or the S modifier to include system objects. If +
	   is appended to the command name, each object is listed with its associated
	   description.

       \dC[+] [ pattern ]
	   Lists type casts. If pattern is specified, only casts whose source or target types
	   match the pattern are listed. If + is appended to the command name, each object is
	   listed with its associated description.

       \dd[S] [ pattern ]
	   Shows the descriptions of objects of type constraint, operator class, operator family,
	   rule, and trigger. All other comments may be viewed by the respective backslash
	   commands for those object types.

	   \dd displays descriptions for objects matching the pattern, or of visible objects of
	   the appropriate type if no argument is given. But in either case, only objects that
	   have a description are listed. By default, only user-created objects are shown; supply
	   a pattern or the S modifier to include system objects.

	   Descriptions for objects can be created with the COMMENT(7) SQL command.

       \ddp [ pattern ]
	   Lists default access privilege settings. An entry is shown for each role (and schema,
	   if applicable) for which the default privilege settings have been changed from the
	   built-in defaults. If pattern is specified, only entries whose role name or schema
	   name matches the pattern are listed.

	   The ALTER DEFAULT PRIVILEGES (ALTER_DEFAULT_PRIVILEGES(7)) command is used to set
	   default access privileges. The meaning of the privilege display is explained under
	   GRANT(7).

       \dD[S+] [ pattern ]
	   Lists domains. If pattern is specified, only domains whose names match the pattern are
	   shown. By default, only user-created objects are shown; supply a pattern or the S
	   modifier to include system objects. If + is appended to the command name, each object
	   is listed with its associated permissions and description.

       \dE[S+] [ pattern ], \di[S+] [ pattern ], \ds[S+] [ pattern ], \dt[S+] [ pattern ],
       \dv[S+] [ pattern ]
	   In this group of commands, the letters E, i, s, t, and v stand for foreign table,
	   index, sequence, table, and view, respectively. You can specify any or all of these
	   letters, in any order, to obtain a listing of objects of these types. For example,
	   \dit lists indexes and tables. If + is appended to the command name, each object is
	   listed with its physical size on disk and its associated description, if any. If
	   pattern is specified, only objects whose names match the pattern are listed. By
	   default, only user-created objects are shown; supply a pattern or the S modifier to
	   include system objects.

       \des[+] [ pattern ]
	   Lists foreign servers (mnemonic: "external servers"). If pattern is specified, only
	   those servers whose name matches the pattern are listed. If the form \des+ is used, a
	   full description of each server is shown, including the server's ACL, type, version,
	   options, and description.

       \det[+] [ pattern ]
	   Lists foreign tables (mnemonic: "external tables"). If pattern is specified, only
	   entries whose table name or schema name matches the pattern are listed. If the form
	   \det+ is used, generic options and the foreign table description are also displayed.

       \deu[+] [ pattern ]
	   Lists user mappings (mnemonic: "external users"). If pattern is specified, only those
	   mappings whose user names match the pattern are listed. If the form \deu+ is used,
	   additional information about each mapping is shown.

	       Caution
	       \deu+ might also display the user name and password of the remote user, so care
	       should be taken not to disclose them.

       \dew[+] [ pattern ]
	   Lists foreign-data wrappers (mnemonic: "external wrappers"). If pattern is specified,
	   only those foreign-data wrappers whose name matches the pattern are listed. If the
	   form \dew+ is used, the ACL, options, and description of the foreign-data wrapper are
	   also shown.

       \df[antwS+] [ pattern ]
	   Lists functions, together with their arguments, return types, and function types,
	   which are classified as "agg" (aggregate), "normal", "trigger", or "window". To
	   display only functions of specific type(s), add the corresponding letters a, n, t, or
	   w to the command. If pattern is specified, only functions whose names match the
	   pattern are shown. If the form \df+ is used, additional information about each
	   function, including volatility, language, source code and description, is shown. By
	   default, only user-created objects are shown; supply a pattern or the S modifier to
	   include system objects.

	       Tip
	       To look up functions taking arguments or returning values of a specific type, use
	       your pager's search capability to scroll through the \df output.

       \dF[+] [ pattern ]
	   Lists text search configurations. If pattern is specified, only configurations whose
	   names match the pattern are shown. If the form \dF+ is used, a full description of
	   each configuration is shown, including the underlying text search parser and the
	   dictionary list for each parser token type.

       \dFd[+] [ pattern ]
	   Lists text search dictionaries. If pattern is specified, only dictionaries whose names
	   match the pattern are shown. If the form \dFd+ is used, additional information is
	   shown about each selected dictionary, including the underlying text search template
	   and the option values.

       \dFp[+] [ pattern ]
	   Lists text search parsers. If pattern is specified, only parsers whose names match the
	   pattern are shown. If the form \dFp+ is used, a full description of each parser is
	   shown, including the underlying functions and the list of recognized token types.

       \dFt[+] [ pattern ]
	   Lists text search templates. If pattern is specified, only templates whose names match
	   the pattern are shown. If the form \dFt+ is used, additional information is shown
	   about each template, including the underlying function names.

       \dg[+] [ pattern ]
	   Lists database roles. (Since the concepts of "users" and "groups" have been unified
	   into "roles", this command is now equivalent to \du.) If pattern is specified, only
	   those roles whose names match the pattern are listed. If the form \dg+ is used,
	   additional information is shown about each role; currently this adds the comment for
	   each role.

       \dl
	   This is an alias for \lo_list, which shows a list of large objects.

       \dL[S+] [ pattern ]
	   Lists procedural languages. If pattern is specified, only languages whose names match
	   the pattern are listed. By default, only user-created languages are shown; supply the
	   S modifier to include system objects. If + is appended to the command name, each
	   language is listed with its call handler, validator, access privileges, and whether it
	   is a system object.

       \dn[S+] [ pattern ]
	   Lists schemas (namespaces). If pattern is specified, only schemas whose names match
	   the pattern are listed. By default, only user-created objects are shown; supply a
	   pattern or the S modifier to include system objects. If + is appended to the command
	   name, each object is listed with its associated permissions and description, if any.

       \do[S] [ pattern ]
	   Lists operators with their operand and return types. If pattern is specified, only
	   operators whose names match the pattern are listed. By default, only user-created
	   objects are shown; supply a pattern or the S modifier to include system objects.

       \dO[S+] [ pattern ]
	   Lists collations. If pattern is specified, only collations whose names match the
	   pattern are listed. By default, only user-created objects are shown; supply a pattern
	   or the S modifier to include system objects. If + is appended to the command name,
	   each collation is listed with its associated description, if any. Note that only
	   collations usable with the current database's encoding are shown, so the results may
	   vary in different databases of the same installation.

       \dp [ pattern ]
	   Lists tables, views and sequences with their associated access privileges. If pattern
	   is specified, only tables, views and sequences whose names match the pattern are
	   listed.

	   The GRANT(7) and REVOKE(7) commands are used to set access privileges. The meaning of
	   the privilege display is explained under GRANT(7).

       \drds [ role-pattern [ database-pattern ] ]
	   Lists defined configuration settings. These settings can be role-specific,
	   database-specific, or both.	role-pattern and database-pattern are used to select
	   specific roles and databases to list, respectively. If omitted, or if * is specified,
	   all settings are listed, including those not role-specific or database-specific,
	   respectively.

	   The ALTER ROLE (ALTER_ROLE(7)) and ALTER DATABASE (ALTER_DATABASE(7)) commands are
	   used to define per-role and per-database configuration settings.

       \dT[S+] [ pattern ]
	   Lists data types. If pattern is specified, only types whose names match the pattern
	   are listed. If + is appended to the command name, each type is listed with its
	   internal name and size, its allowed values if it is an enum type, and its associated
	   permissions. By default, only user-created objects are shown; supply a pattern or the
	   S modifier to include system objects.

       \du[+] [ pattern ]
	   Lists database roles. (Since the concepts of "users" and "groups" have been unified
	   into "roles", this command is now equivalent to \dg.) If pattern is specified, only
	   those roles whose names match the pattern are listed. If the form \du+ is used,
	   additional information is shown about each role; currently this adds the comment for
	   each role.

       \dx[+] [ pattern ]
	   Lists installed extensions. If pattern is specified, only those extensions whose names
	   match the pattern are listed. If the form \dx+ is used, all the objects belonging to
	   each matching extension are listed.

       \e or \edit [ filename ] [ line_number ]
	   If filename is specified, the file is edited; after the editor exits, its content is
	   copied back to the query buffer. If no filename is given, the current query buffer is
	   copied to a temporary file which is then edited in the same fashion.

	   The new query buffer is then re-parsed according to the normal rules of psql, where
	   the whole buffer is treated as a single line. (Thus you cannot make scripts this way.
	   Use \i for that.) This means that if the query ends with (or contains) a semicolon, it
	   is immediately executed. Otherwise it will merely wait in the query buffer; type
	   semicolon or \g to send it, or \r to cancel.

	   If a line number is specified, psql will position the cursor on the specified line of
	   the file or query buffer. Note that if a single all-digits argument is given, psql
	   assumes it is a line number, not a file name.

	       Tip
	       See under ENVIRONMENT for how to configure and customize your editor.

       \echo text [ ... ]
	   Prints the arguments to the standard output, separated by one space and followed by a
	   newline. This can be useful to intersperse information in the output of scripts. For
	   example:

	       => \echo `date`
	       Tue Oct 26 21:40:57 CEST 1999

	   If the first argument is an unquoted -n the trailing newline is not written.

	       Tip
	       If you use the \o command to redirect your query output you might wish to use
	       \qecho instead of this command.

       \ef [ function_description [ line_number ] ]
	   This command fetches and edits the definition of the named function, in the form of a
	   CREATE OR REPLACE FUNCTION command. Editing is done in the same way as for \edit.
	   After the editor exits, the updated command waits in the query buffer; type semicolon
	   or \g to send it, or \r to cancel.

	   The target function can be specified by name alone, or by name and arguments, for
	   example foo(integer, text). The argument types must be given if there is more than one
	   function of the same name.

	   If no function is specified, a blank CREATE FUNCTION template is presented for
	   editing.

	   If a line number is specified, psql will position the cursor on the specified line of
	   the function body. (Note that the function body typically does not begin on the first
	   line of the file.)

	       Tip
	       See under ENVIRONMENT for how to configure and customize your editor.

       \encoding [ encoding ]
	   Sets the client character set encoding. Without an argument, this command shows the
	   current encoding.

       \f [ string ]
	   Sets the field separator for unaligned query output. The default is the vertical bar
	   (|). See also \pset for a generic way of setting output options.

       \g [ { filename | |command } ]
	   Sends the current query input buffer to the server and optionally stores the query's
	   output in filename or pipes the output into a separate Unix shell executing command. A
	   bare \g is virtually equivalent to a semicolon. A \g with argument is a "one-shot"
	   alternative to the \o command.

       \h or \help [ command ]
	   Gives syntax help on the specified SQL command. If command is not specified, then psql
	   will list all the commands for which syntax help is available. If command is an
	   asterisk (*), then syntax help on all SQL commands is shown.

	       Note
	       To simplify typing, commands that consists of several words do not have to be
	       quoted. Thus it is fine to type \help alter table.

       \H
	   Turns on HTML query output format. If the HTML format is already on, it is switched
	   back to the default aligned text format. This command is for compatibility and
	   convenience, but see \pset about setting other output options.

       \i filename
	   Reads input from the file filename and executes it as though it had been typed on the
	   keyboard.

	       Note
	       If you want to see the lines on the screen as they are read you must set the
	       variable ECHO to all.

       \ir filename
	   The \ir command is similar to \i, but resolves relative file names differently. When
	   executing in interactive mode, the two commands behave identically. However, when
	   invoked from a script, \ir interprets file names relative to the directory in which
	   the script is located, rather than the current working directory.

       \l (or \list), \l+ (or \list+)
	   List the names, owners, character set encodings, and access privileges of all the
	   databases in the server. If + is appended to the command name, database sizes, default
	   tablespaces, and descriptions are also displayed. (Size information is only available
	   for databases that the current user can connect to.)

       \lo_export loid filename
	   Reads the large object with OID loid from the database and writes it to filename. Note
	   that this is subtly different from the server function lo_export, which acts with the
	   permissions of the user that the database server runs as and on the server's file
	   system.

	       Tip
	       Use \lo_list to find out the large object's OID.

       \lo_import filename [ comment ]
	   Stores the file into a PostgreSQL large object. Optionally, it associates the given
	   comment with the object. Example:

	       foo=> \lo_import '/home/peter/pictures/photo.xcf' 'a picture of me'
	       lo_import 152801

	   The response indicates that the large object received object ID 152801, which can be
	   used to access the newly-created large object in the future. For the sake of
	   readability, it is recommended to always associate a human-readable comment with every
	   object. Both OIDs and comments can be viewed with the \lo_list command.

	   Note that this command is subtly different from the server-side lo_import because it
	   acts as the local user on the local file system, rather than the server's user and
	   file system.

       \lo_list
	   Shows a list of all PostgreSQL large objects currently stored in the database, along
	   with any comments provided for them.

       \lo_unlink loid
	   Deletes the large object with OID loid from the database.

	       Tip
	       Use \lo_list to find out the large object's OID.

       \o [ {filename | |command} ]
	   Saves future query results to the file filename or pipes future results into a
	   separate Unix shell to execute command. If no arguments are specified, the query
	   output will be reset to the standard output.

	   "Query results" includes all tables, command responses, and notices obtained from the
	   database server, as well as output of various backslash commands that query the
	   database (such as \d), but not error messages.

	       Tip
	       To intersperse text output in between query results, use \qecho.

       \p
	   Print the current query buffer to the standard output.

       \password [ username ]
	   Changes the password of the specified user (by default, the current user). This
	   command prompts for the new password, encrypts it, and sends it to the server as an
	   ALTER ROLE command. This makes sure that the new password does not appear in cleartext
	   in the command history, the server log, or elsewhere.

       \prompt [ text ] name
	   Prompts the user to supply text, which is assigned to the variable name. An optional
	   prompt string, text, can be specified. (For multiword prompts, surround the text with
	   single quotes.)

	   By default, \prompt uses the terminal for input and output. However, if the -f command
	   line switch was used, \prompt uses standard input and standard output.

       \pset option [ value ]
	   This command sets options affecting the output of query result tables.  option
	   indicates which option is to be set. The semantics of value vary depending on the
	   selected option. For some options, omitting value causes the option to be toggled or
	   unset, as described under the particular option. If no such behavior is mentioned,
	   then omitting value just results in the current setting being displayed.

	   Adjustable printing options are:

	   border
	       The value must be a number. In general, the higher the number the more borders and
	       lines the tables will have, but this depends on the particular format. In HTML
	       format, this will translate directly into the border=...  attribute; in the other
	       formats only values 0 (no border), 1 (internal dividing lines), and 2 (table
	       frame) make sense.

	   columns
	       Sets the target width for the wrapped format, and also the width limit for
	       determining whether output is wide enough to require the pager or switch to the
	       vertical display in expanded auto mode. Zero (the default) causes the target width
	       to be controlled by the environment variable COLUMNS, or the detected screen width
	       if COLUMNS is not set. In addition, if columns is zero then the wrapped format
	       only affects screen output. If columns is nonzero then file and pipe output is
	       wrapped to that width as well.

	   expanded (or x)
	       If value is specified it must be either on or off, which will enable or disable
	       expanded mode, or auto. If value is omitted the command toggles between the on and
	       off settings. When expanded mode is enabled, query results are displayed in two
	       columns, with the column name on the left and the data on the right. This mode is
	       useful if the data wouldn't fit on the screen in the normal "horizontal" mode. In
	       the auto setting, the expanded mode is used whenever the query output is wider
	       than the screen, otherwise the regular mode is used. The auto setting is only
	       effective in the aligned and wrapped formats. In other formats, it always behaves
	       as if the expanded mode is off.

	   fieldsep
	       Specifies the field separator to be used in unaligned output format. That way one
	       can create, for example, tab- or comma-separated output, which other programs
	       might prefer. To set a tab as field separator, type \pset fieldsep '\t'. The
	       default field separator is '|' (a vertical bar).

	   fieldsep_zero
	       Sets the field separator to use in unaligned output format to a zero byte.

	   footer
	       If value is specified it must be either on or off which will enable or disable
	       display of the table footer (the (n rows) count). If value is omitted the command
	       toggles footer display on or off.

	   format
	       Sets the output format to one of unaligned, aligned, wrapped, html, latex, or
	       troff-ms. Unique abbreviations are allowed. (That would mean one letter is
	       enough.)

	       unaligned format writes all columns of a row on one line, separated by the
	       currently active field separator. This is useful for creating output that might be
	       intended to be read in by other programs (for example, tab-separated or
	       comma-separated format).

	       aligned format is the standard, human-readable, nicely formatted text output; this
	       is the default.

	       wrapped format is like aligned but wraps wide data values across lines to make the
	       output fit in the target column width. The target width is determined as described
	       under the columns option. Note that psql will not attempt to wrap column header
	       titles; therefore, wrapped format behaves the same as aligned if the total width
	       needed for column headers exceeds the target.

	       The html, latex, and troff-ms formats put out tables that are intended to be
	       included in documents using the respective mark-up language. They are not complete
	       documents! (This might not be so dramatic in HTML, but in LaTeX you must have a
	       complete document wrapper.)

	   linestyle
	       Sets the border line drawing style to one of ascii, old-ascii or unicode. Unique
	       abbreviations are allowed. (That would mean one letter is enough.) The default
	       setting is ascii. This option only affects the aligned and wrapped output formats.

	       ascii style uses plain ASCII characters. Newlines in data are shown using a +
	       symbol in the right-hand margin. When the wrapped format wraps data from one line
	       to the next without a newline character, a dot (.) is shown in the right-hand
	       margin of the first line, and again in the left-hand margin of the following line.

	       old-ascii style uses plain ASCII characters, using the formatting style used in
	       PostgreSQL 8.4 and earlier. Newlines in data are shown using a : symbol in place
	       of the left-hand column separator. When the data is wrapped from one line to the
	       next without a newline character, a ; symbol is used in place of the left-hand
	       column separator.

	       unicode style uses Unicode box-drawing characters. Newlines in data are shown
	       using a carriage return symbol in the right-hand margin. When the data is wrapped
	       from one line to the next without a newline character, an ellipsis symbol is shown
	       in the right-hand margin of the first line, and again in the left-hand margin of
	       the following line.

	       When the border setting is greater than zero, this option also determines the
	       characters with which the border lines are drawn. Plain ASCII characters work
	       everywhere, but Unicode characters look nicer on displays that recognize them.

	   null
	       Sets the string to be printed in place of a null value. The default is to print
	       nothing, which can easily be mistaken for an empty string. For example, one might
	       prefer \pset null '(null)'.

	   numericlocale
	       If value is specified it must be either on or off which will enable or disable
	       display of a locale-specific character to separate groups of digits to the left of
	       the decimal marker. If value is omitted the command toggles between regular and
	       locale-specific numeric output.

	   pager
	       Controls use of a pager program for query and psql help output. If the environment
	       variable PAGER is set, the output is piped to the specified program. Otherwise a
	       platform-dependent default (such as more) is used.

	       When the pager option is off, the pager program is not used. When the pager option
	       is on, the pager is used when appropriate, i.e., when the output is to a terminal
	       and will not fit on the screen. The pager option can also be set to always, which
	       causes the pager to be used for all terminal output regardless of whether it fits
	       on the screen.  \pset pager without a value toggles pager use on and off.

	   recordsep
	       Specifies the record (line) separator to use in unaligned output format. The
	       default is a newline character.

	   recordsep_zero
	       Sets the record separator to use in unaligned output format to a zero byte.

	   tableattr (or T)
	       Specifies attributes to be placed inside the HTML table tag in html output format.
	       This could for example be cellpadding or bgcolor. Note that you probably don't
	       want to specify border here, as that is already taken care of by \pset border. If
	       no value is given, the table attributes are unset.

	   title
	       Sets the table title for any subsequently printed tables. This can be used to give
	       your output descriptive tags. If no value is given, the title is unset.

	   tuples_only (or t)
	       If value is specified it must be either on or off which will enable or disable
	       tuples-only mode. If value is omitted the command toggles between regular and
	       tuples-only output. Regular output includes extra information such as column
	       headers, titles, and various footers. In tuples-only mode, only actual table data
	       is shown.

	   Illustrations of how these different formats look can be seen in the EXAMPLES section.

	       Tip
	       There are various shortcut commands for \pset. See \a, \C, \H, \t, \T, and \x.

	       Note
	       It is an error to call \pset without any arguments. In the future this case might
	       show the current status of all printing options.

       \q or \quit
	   Quits the psql program. In a script file, only execution of that script is terminated.

       \qecho text [ ... ]
	   This command is identical to \echo except that the output will be written to the query
	   output channel, as set by \o.

       \r
	   Resets (clears) the query buffer.

       \s [ filename ]
	   Print or save the command line history to filename. If filename is omitted, the
	   history is written to the standard output. This option is only available if psql is
	   configured to use the GNU Readline library.

       \set [ name [ value [ ... ] ] ]
	   Sets the psql variable name to value, or if more than one value is given, to the
	   concatenation of all of them. If only one argument is given, the variable is set with
	   an empty value. To unset a variable, use the \unset command.

	   \set without any arguments displays the names and values of all currently-set psql
	   variables.

	   Valid variable names can contain letters, digits, and underscores. See the section
	   Variables below for details. Variable names are case-sensitive.

	   Although you are welcome to set any variable to anything you want, psql treats several
	   variables as special. They are documented in the section about variables.

	       Note
	       This command is unrelated to the SQL command SET(7).

       \setenv [ name [ value ] ]
	   Sets the environment variable name to value, or if the value is not supplied, unsets
	   the environment variable. Example:

	       testdb=> \setenv PAGER less
	       testdb=> \setenv LESS -imx4F

       \sf[+] function_description
	   This command fetches and shows the definition of the named function, in the form of a
	   CREATE OR REPLACE FUNCTION command. The definition is printed to the current query
	   output channel, as set by \o.

	   The target function can be specified by name alone, or by name and arguments, for
	   example foo(integer, text). The argument types must be given if there is more than one
	   function of the same name.

	   If + is appended to the command name, then the output lines are numbered, with the
	   first line of the function body being line 1.

       \t
	   Toggles the display of output column name headings and row count footer. This command
	   is equivalent to \pset tuples_only and is provided for convenience.

       \T table_options
	   Specifies attributes to be placed within the table tag in HTML output format. This
	   command is equivalent to \pset tableattr table_options.

       \timing [ on | off ]
	   Without parameter, toggles a display of how long each SQL statement takes, in
	   milliseconds. With parameter, sets same.

       \unset name
	   Unsets (deletes) the psql variable name.

       \w filename, \w |command
	   Outputs the current query buffer to the file filename or pipes it to the Unix command
	   command.

       \x [ on | off | auto ]
	   Sets or toggles expanded table formatting mode. As such it is equivalent to \pset
	   expanded.

       \z [ pattern ]
	   Lists tables, views and sequences with their associated access privileges. If a
	   pattern is specified, only tables, views and sequences whose names match the pattern
	   are listed.

	   This is an alias for \dp ("display privileges").

       \! [ command ]
	   Escapes to a separate Unix shell or executes the Unix command command. The arguments
	   are not further interpreted; the shell will see them as-is.

       \?
	   Shows help information about the backslash commands.

       Patterns
	   The various \d commands accept a pattern parameter to specify the object name(s) to be
	   displayed. In the simplest case, a pattern is just the exact name of the object. The
	   characters within a pattern are normally folded to lower case, just as in SQL names;
	   for example, \dt FOO will display the table named foo. As in SQL names, placing double
	   quotes around a pattern stops folding to lower case. Should you need to include an
	   actual double quote character in a pattern, write it as a pair of double quotes within
	   a double-quote sequence; again this is in accord with the rules for SQL quoted
	   identifiers. For example, \dt "FOO""BAR" will display the table named FOO"BAR (not
	   foo"bar). Unlike the normal rules for SQL names, you can put double quotes around just
	   part of a pattern, for instance \dt FOO"FOO"BAR will display the table named
	   fooFOObar.

	   Whenever the pattern parameter is omitted completely, the \d commands display all
	   objects that are visible in the current schema search path -- this is equivalent to
	   using * as the pattern. (An object is said to be visible if its containing schema is
	   in the search path and no object of the same kind and name appears earlier in the
	   search path. This is equivalent to the statement that the object can be referenced by
	   name without explicit schema qualification.) To see all objects in the database
	   regardless of visibility, use *.*  as the pattern.

	   Within a pattern, * matches any sequence of characters (including no characters) and ?
	   matches any single character. (This notation is comparable to Unix shell file name
	   patterns.) For example, \dt int* displays tables whose names begin with int. But
	   within double quotes, * and ?  lose these special meanings and are just matched
	   literally.

	   A pattern that contains a dot (.) is interpreted as a schema name pattern followed by
	   an object name pattern. For example, \dt foo*.*bar* displays all tables whose table
	   name includes bar that are in schemas whose schema name starts with foo. When no dot
	   appears, then the pattern matches only objects that are visible in the current schema
	   search path. Again, a dot within double quotes loses its special meaning and is
	   matched literally.

	   Advanced users can use regular-expression notations such as character classes, for
	   example [0-9] to match any digit. All regular expression special characters work as
	   specified in Section 9.7.3, "POSIX Regular Expressions", in the documentation, except
	   for .  which is taken as a separator as mentioned above, * which is translated to the
	   regular-expression notation .*, ?  which is translated to ., and $ which is matched
	   literally. You can emulate these pattern characters at need by writing ?  for ., (R+|)
	   for R*, or (R|) for R?.  $ is not needed as a regular-expression character since the
	   pattern must match the whole name, unlike the usual interpretation of regular
	   expressions (in other words, $ is automatically appended to your pattern). Write * at
	   the beginning and/or end if you don't wish the pattern to be anchored. Note that
	   within double quotes, all regular expression special characters lose their special
	   meanings and are matched literally. Also, the regular expression special characters
	   are matched literally in operator name patterns (i.e., the argument of \do).

   Advanced Features
       Variables
	   psql provides variable substitution features similar to common Unix command shells.
	   Variables are simply name/value pairs, where the value can be any string of any
	   length. The name must consist of letters (including non-Latin letters), digits, and
	   underscores.

	   To set a variable, use the psql meta-command \set. For example,

	       testdb=> \set foo bar

	   sets the variable foo to the value bar. To retrieve the content of the variable,
	   precede the name with a colon, for example:

	       testdb=> \echo :foo
	       bar

	   This works in both regular SQL commands and meta-commands; there is more detail in SQL
	   Interpolation, below.

	   If you call \set without a second argument, the variable is set, with an empty string
	   as value. To unset (i.e., delete) a variable, use the command \unset. To show the
	   values of all variables, call \set without any argument.

	       Note
	       The arguments of \set are subject to the same substitution rules as with other
	       commands. Thus you can construct interesting references such as \set :foo
	       'something' and get "soft links" or "variable variables" of Perl or PHP fame,
	       respectively. Unfortunately (or fortunately?), there is no way to do anything
	       useful with these constructs. On the other hand, \set bar :foo is a perfectly
	       valid way to copy a variable.

	   A number of these variables are treated specially by psql. They represent certain
	   option settings that can be changed at run time by altering the value of the variable,
	   or in some cases represent changeable state of psql. Although you can use these
	   variables for other purposes, this is not recommended, as the program behavior might
	   grow really strange really quickly. By convention, all specially treated variables'
	   names consist of all upper-case ASCII letters (and possibly digits and underscores).
	   To ensure maximum compatibility in the future, avoid using such variable names for
	   your own purposes. A list of all specially treated variables follows.

	   AUTOCOMMIT
	       When on (the default), each SQL command is automatically committed upon successful
	       completion. To postpone commit in this mode, you must enter a BEGIN or START
	       TRANSACTION SQL command. When off or unset, SQL commands are not committed until
	       you explicitly issue COMMIT or END. The autocommit-off mode works by issuing an
	       implicit BEGIN for you, just before any command that is not already in a
	       transaction block and is not itself a BEGIN or other transaction-control command,
	       nor a command that cannot be executed inside a transaction block (such as VACUUM).

		   Note
		   In autocommit-off mode, you must explicitly abandon any failed transaction by
		   entering ABORT or ROLLBACK. Also keep in mind that if you exit the session
		   without committing, your work will be lost.

		   Note
		   The autocommit-on mode is PostgreSQL's traditional behavior, but
		   autocommit-off is closer to the SQL spec. If you prefer autocommit-off, you
		   might wish to set it in the system-wide psqlrc file or your ~/.psqlrc file.

	   COMP_KEYWORD_CASE
	       Determines which letter case to use when completing an SQL key word. If set to
	       lower or upper, the completed word will be in lower or upper case, respectively.
	       If set to preserve-lower or preserve-upper (the default), the completed word will
	       be in the case of the word already entered, but words being completed without
	       anything entered will be in lower or upper case, respectively.

	   DBNAME
	       The name of the database you are currently connected to. This is set every time
	       you connect to a database (including program start-up), but can be unset.

	   ECHO
	       If set to all, all lines entered from the keyboard or from a script are written to
	       the standard output before they are parsed or executed. To select this behavior on
	       program start-up, use the switch -a. If set to queries, psql merely prints all
	       queries as they are sent to the server. The switch for this is -e.

	   ECHO_HIDDEN
	       When this variable is set and a backslash command queries the database, the query
	       is first shown. This way you can study the PostgreSQL internals and provide
	       similar functionality in your own programs. (To select this behavior on program
	       start-up, use the switch -E.) If you set the variable to the value noexec, the
	       queries are just shown but are not actually sent to the server and executed.

	   ENCODING
	       The current client character set encoding.

	   FETCH_COUNT
	       If this variable is set to an integer value > 0, the results of SELECT queries are
	       fetched and displayed in groups of that many rows, rather than the default
	       behavior of collecting the entire result set before display. Therefore only a
	       limited amount of memory is used, regardless of the size of the result set.
	       Settings of 100 to 1000 are commonly used when enabling this feature. Keep in mind
	       that when using this feature, a query might fail after having already displayed
	       some rows.

		   Tip
		   Although you can use any output format with this feature, the default aligned
		   format tends to look bad because each group of FETCH_COUNT rows will be
		   formatted separately, leading to varying column widths across the row groups.
		   The other output formats work better.

	   HISTCONTROL
	       If this variable is set to ignorespace, lines which begin with a space are not
	       entered into the history list. If set to a value of ignoredups, lines matching the
	       previous history line are not entered. A value of ignoreboth combines the two
	       options. If unset, or if set to any other value than those above, all lines read
	       in interactive mode are saved on the history list.

		   Note
		   This feature was shamelessly plagiarized from Bash.

	   HISTFILE
	       The file name that will be used to store the history list. The default value is
	       ~/.psql_history. For example, putting:

		   \set HISTFILE ~/.psql_history- :DBNAME

	       in ~/.psqlrc will cause psql to maintain a separate history for each database.

		   Note
		   This feature was shamelessly plagiarized from Bash.

	   HISTSIZE
	       The number of commands to store in the command history. The default value is 500.

		   Note
		   This feature was shamelessly plagiarized from Bash.

	   HOST
	       The database server host you are currently connected to. This is set every time
	       you connect to a database (including program start-up), but can be unset.

	   IGNOREEOF
	       If unset, sending an EOF character (usually Control+D) to an interactive session
	       of psql will terminate the application. If set to a numeric value, that many EOF
	       characters are ignored before the application terminates. If the variable is set
	       but has no numeric value, the default is 10.

		   Note
		   This feature was shamelessly plagiarized from Bash.

	   LASTOID
	       The value of the last affected OID, as returned from an INSERT or \lo_import
	       command. This variable is only guaranteed to be valid until after the result of
	       the next SQL command has been displayed.

	   ON_ERROR_ROLLBACK
	       When on, if a statement in a transaction block generates an error, the error is
	       ignored and the transaction continues. When interactive, such errors are only
	       ignored in interactive sessions, and not when reading script files. When off (the
	       default), a statement in a transaction block that generates an error aborts the
	       entire transaction. The on_error_rollback-on mode works by issuing an implicit
	       SAVEPOINT for you, just before each command that is in a transaction block, and
	       rolls back to the savepoint on error.

	   ON_ERROR_STOP
	       By default, command processing continues after an error. When this variable is
	       set, it will instead stop immediately. In interactive mode, psql will return to
	       the command prompt; otherwise, psql will exit, returning error code 3 to
	       distinguish this case from fatal error conditions, which are reported using error
	       code 1. In either case, any currently running scripts (the top-level script, if
	       any, and any other scripts which it may have in invoked) will be terminated
	       immediately. If the top-level command string contained multiple SQL commands,
	       processing will stop with the current command.

	   PORT
	       The database server port to which you are currently connected. This is set every
	       time you connect to a database (including program start-up), but can be unset.

	   PROMPT1, PROMPT2, PROMPT3
	       These specify what the prompts psql issues should look like. See Prompting below.

	   QUIET
	       This variable is equivalent to the command line option -q. It is probably not too
	       useful in interactive mode.

	   SINGLELINE
	       This variable is equivalent to the command line option -S.

	   SINGLESTEP
	       This variable is equivalent to the command line option -s.

	   USER
	       The database user you are currently connected as. This is set every time you
	       connect to a database (including program start-up), but can be unset.

	   VERBOSITY
	       This variable can be set to the values default, verbose, or terse to control the
	       verbosity of error reports.

       SQL Interpolation
	   A key feature of psql variables is that you can substitute ("interpolate") them into
	   regular SQL statements, as well as the arguments of meta-commands. Furthermore, psql
	   provides facilities for ensuring that variable values used as SQL literals and
	   identifiers are properly quoted. The syntax for interpolating a value without any
	   quoting is to prepend the variable name with a colon (:). For example,

	       testdb=> \set foo 'my_table'
	       testdb=> SELECT * FROM :foo;

	   would query the table my_table. Note that this may be unsafe: the value of the
	   variable is copied literally, so it can contain unbalanced quotes, or even backslash
	   commands. You must make sure that it makes sense where you put it.

	   When a value is to be used as an SQL literal or identifier, it is safest to arrange
	   for it to be quoted. To quote the value of a variable as an SQL literal, write a colon
	   followed by the variable name in single quotes. To quote the value as an SQL
	   identifier, write a colon followed by the variable name in double quotes. These
	   constructs deal correctly with quotes and other special characters embedded within the
	   variable value. The previous example would be more safely written this way:

	       testdb=> \set foo 'my_table'
	       testdb=> SELECT * FROM :"foo";

	   Variable interpolation will not be performed within quoted SQL literals and
	   identifiers. Therefore, a construction such as ':foo' doesn't work to produce a quoted
	   literal from a variable's value (and it would be unsafe if it did work, since it
	   wouldn't correctly handle quotes embedded in the value).

	   One example use of this mechanism is to copy the contents of a file into a table
	   column. First load the file into a variable and then interpolate the variable's value
	   as a quoted string:

	       testdb=> \set content `cat my_file.txt`
	       testdb=> INSERT INTO my_table VALUES (:'content');

	   (Note that this still won't work if my_file.txt contains NUL bytes.	psql does not
	   support embedded NUL bytes in variable values.)

	   Since colons can legally appear in SQL commands, an apparent attempt at interpolation
	   (that is, :name, :'name', or :"name") is not replaced unless the named variable is
	   currently set. In any case, you can escape a colon with a backslash to protect it from
	   substitution.

	   The colon syntax for variables is standard SQL for embedded query languages, such as
	   ECPG. The colon syntaxes for array slices and type casts are PostgreSQL extensions,
	   which can sometimes conflict with the standard usage. The colon-quote syntax for
	   escaping a variable's value as an SQL literal or identifier is a psql extension.

       Prompting
	   The prompts psql issues can be customized to your preference. The three variables
	   PROMPT1, PROMPT2, and PROMPT3 contain strings and special escape sequences that
	   describe the appearance of the prompt. Prompt 1 is the normal prompt that is issued
	   when psql requests a new command. Prompt 2 is issued when more input is expected
	   during command input because the command was not terminated with a semicolon or a
	   quote was not closed. Prompt 3 is issued when you run an SQL COPY command and you are
	   expected to type in the row values on the terminal.

	   The value of the selected prompt variable is printed literally, except where a percent
	   sign (%) is encountered. Depending on the next character, certain other text is
	   substituted instead. Defined substitutions are:

	   %M
	       The full host name (with domain name) of the database server, or [local] if the
	       connection is over a Unix domain socket, or [local:/dir/name], if the Unix domain
	       socket is not at the compiled in default location.

	   %m
	       The host name of the database server, truncated at the first dot, or [local] if
	       the connection is over a Unix domain socket.

	   %>
	       The port number at which the database server is listening.

	   %n
	       The database session user name. (The expansion of this value might change during a
	       database session as the result of the command SET SESSION AUTHORIZATION.)

	   %/
	       The name of the current database.

	   %~
	       Like %/, but the output is ~ (tilde) if the database is your default database.

	   %#
	       If the session user is a database superuser, then a #, otherwise a >. (The
	       expansion of this value might change during a database session as the result of
	       the command SET SESSION AUTHORIZATION.)

	   %R
	       In prompt 1 normally =, but ^ if in single-line mode, and !  if the session is
	       disconnected from the database (which can happen if \connect fails). In prompt 2
	       the sequence is replaced by -, *, a single quote, a double quote, or a dollar
	       sign, depending on whether psql expects more input because the command wasn't
	       terminated yet, because you are inside a /* ... */ comment, or because you are
	       inside a quoted or dollar-escaped string. In prompt 3 the sequence doesn't produce
	       anything.

	   %x
	       Transaction status: an empty string when not in a transaction block, or * when in
	       a transaction block, or !  when in a failed transaction block, or ?  when the
	       transaction state is indeterminate (for example, because there is no connection).

	   %digits
	       The character with the indicated octal code is substituted.

	   %:name:
	       The value of the psql variable name. See the section Variables for details.

	   %`command`
	       The output of command, similar to ordinary "back-tick" substitution.

	   %[ ... %]
	       Prompts can contain terminal control characters which, for example, change the
	       color, background, or style of the prompt text, or change the title of the
	       terminal window. In order for the line editing features of Readline to work
	       properly, these non-printing control characters must be designated as invisible by
	       surrounding them with %[ and %]. Multiple pairs of these can occur within the
	       prompt. For example:

		   testdb=> \set PROMPT1 '%[%033[1;33;40m%]%n@%/%R%[%033[0m%]%# '

	       results in a boldfaced (1;) yellow-on-black (33;40) prompt on VT100-compatible,
	       color-capable terminals.
	   To insert a percent sign into your prompt, write %%. The default prompts are '%/%R%# '
	   for prompts 1 and 2, and '>> ' for prompt 3.

	       Note
	       This feature was shamelessly plagiarized from tcsh.

       Command-Line Editing
	   psql supports the Readline library for convenient line editing and retrieval. The
	   command history is automatically saved when psql exits and is reloaded when psql
	   starts up. Tab-completion is also supported, although the completion logic makes no
	   claim to be an SQL parser. If for some reason you do not like the tab completion, you
	   can turn it off by putting this in a file named .inputrc in your home directory:

	       $if psql
	       set disable-completion on
	       $endif

	   (This is not a psql but a Readline feature. Read its documentation for further
	   details.)

ENVIRONMENT
       COLUMNS
	   If \pset columns is zero, controls the width for the wrapped format and width for
	   determining if wide output requires the pager or should be switched to the vertical
	   format in expanded auto mode.

       PAGER
	   If the query results do not fit on the screen, they are piped through this command.
	   Typical values are more or less. The default is platform-dependent. The use of the
	   pager can be disabled by using the \pset command.

       PGDATABASE, PGHOST, PGPORT, PGUSER
	   Default connection parameters (see Section 31.14, "Environment Variables", in the
	   documentation).

       PSQL_EDITOR, EDITOR, VISUAL
	   Editor used by the \e and \ef commands. The variables are examined in the order
	   listed; the first that is set is used.

	   The built-in default editors are vi on Unix systems and notepad.exe on Windows
	   systems.

       PSQL_EDITOR_LINENUMBER_ARG
	   When \e or \ef is used with a line number argument, this variable specifies the
	   command-line argument used to pass the starting line number to the user's editor. For
	   editors such as Emacs or vi, this is a plus sign. Include a trailing space in the
	   value of the variable if there needs to be space between the option name and the line
	   number. Examples:

	       PSQL_EDITOR_LINENUMBER_ARG='+'
	       PSQL_EDITOR_LINENUMBER_ARG='--line '

	   The default is + on Unix systems (corresponding to the default editor vi, and useful
	   for many other common editors); but there is no default on Windows systems.

       PSQL_HISTORY
	   Alternative location for the command history file. Tilde (~) expansion is performed.

       PSQLRC
	   Alternative location of the user's .psqlrc file. Tilde (~) expansion is performed.

       SHELL
	   Command executed by the \!  command.

       TMPDIR
	   Directory for storing temporary files. The default is /tmp.

       This utility, like most other PostgreSQL utilities, also uses the environment variables
       supported by libpq (see Section 31.14, "Environment Variables", in the documentation).

FILES
       psqlrc and ~/.psqlrc
	   Unless it is passed an -X or -c option, psql attempts to read and execute commands
	   from the system-wide startup file (psqlrc) and then the user's personal startup file
	   (~/.psqlrc), after connecting to the database but before accepting normal commands.
	   These files can be used to set up the client and/or the server to taste, typically
	   with \set and SET commands.

	   The system-wide startup file is named psqlrc and is sought in the installation's
	   "system configuration" directory, which is most reliably identified by running
	   pg_config --sysconfdir. By default this directory will be ../etc/ relative to the
	   directory containing the PostgreSQL executables. The name of this directory can be set
	   explicitly via the PGSYSCONFDIR environment variable.

	   The user's personal startup file is named .psqlrc and is sought in the invoking user's
	   home directory. On Windows, which lacks such a concept, the personal startup file is
	   named %APPDATA%\postgresql\psqlrc.conf. The location of the user's startup file can be
	   set explicitly via the PSQLRC environment variable.

	   Both the system-wide startup file and the user's personal startup file can be made
	   psql-version-specific by appending a dash and the PostgreSQL major or minor release
	   number to the file name, for example ~/.psqlrc-9.2 or ~/.psqlrc-9.2.5. The most
	   specific version-matching file will be read in preference to a non-version-specific
	   file.

       .psql_history
	   The command-line history is stored in the file ~/.psql_history, or
	   %APPDATA%\postgresql\psql_history on Windows.

	   The location of the history file can be set explicitly via the PSQL_HISTORY
	   environment variable.

NOTES
       o   In an earlier life psql allowed the first argument of a single-letter backslash
	   command to start directly after the command, without intervening whitespace. As of
	   PostgreSQL 8.4 this is no longer allowed.

       o   psql is only guaranteed to work smoothly with servers of the same version. That does
	   not mean other combinations will fail outright, but subtle and not-so-subtle problems
	   might come up. Backslash commands are particularly likely to fail if the server is of
	   a newer version than psql itself. However, backslash commands of the \d family should
	   work with servers of versions back to 7.4, though not necessarily with servers newer
	   than psql itself.

NOTES FOR WINDOWS USERS
       psql is built as a "console application". Since the Windows console windows use a
       different encoding than the rest of the system, you must take special care when using
       8-bit characters within psql. If psql detects a problematic console code page, it will
       warn you at startup. To change the console code page, two things are necessary:

       o   Set the code page by entering cmd.exe /c chcp 1252. (1252 is a code page that is
	   appropriate for German; replace it with your value.) If you are using Cygwin, you can
	   put this command in /etc/profile.

       o   Set the console font to Lucida Console, because the raster font does not work with the
	   ANSI code page.

EXAMPLES
       The first example shows how to spread a command over several lines of input. Notice the
       changing prompt:

	   testdb=> CREATE TABLE my_table (
	   testdb(>  first integer not null default 0,
	   testdb(>  second text)
	   testdb-> ;
	   CREATE TABLE

       Now look at the table definition again:

	   testdb=> \d my_table
			Table "my_table"
	    Attribute |  Type	|      Modifier
	   -----------+---------+--------------------
	    first     | integer | not null default 0
	    second    | text	|

       Now we change the prompt to something more interesting:

	   testdb=> \set PROMPT1 '%n@%m %~%R%# '
	   peter@localhost testdb=>

       Let's assume you have filled the table with data and want to take a look at it:

	   peter@localhost testdb=> SELECT * FROM my_table;
	    first | second
	   -------+--------
		1 | one
		2 | two
		3 | three
		4 | four
	   (4 rows)

       You can display tables in different ways by using the \pset command:

	   peter@localhost testdb=> \pset border 2
	   Border style is 2.
	   peter@localhost testdb=> SELECT * FROM my_table;
	   +-------+--------+
	   | first | second |
	   +-------+--------+
	   |	 1 | one    |
	   |	 2 | two    |
	   |	 3 | three  |
	   |	 4 | four   |
	   +-------+--------+
	   (4 rows)

	   peter@localhost testdb=> \pset border 0
	   Border style is 0.
	   peter@localhost testdb=> SELECT * FROM my_table;
	   first second
	   ----- ------
	       1 one
	       2 two
	       3 three
	       4 four
	   (4 rows)

	   peter@localhost testdb=> \pset border 1
	   Border style is 1.
	   peter@localhost testdb=> \pset format unaligned
	   Output format is unaligned.
	   peter@localhost testdb=> \pset fieldsep ","
	   Field separator is ",".
	   peter@localhost testdb=> \pset tuples_only
	   Showing only tuples.
	   peter@localhost testdb=> SELECT second, first FROM my_table;
	   one,1
	   two,2
	   three,3
	   four,4

       Alternatively, use the short commands:

	   peter@localhost testdb=> \a \t \x
	   Output format is aligned.
	   Tuples only is off.
	   Expanded display is on.
	   peter@localhost testdb=> SELECT * FROM my_table;
	   -[ RECORD 1 ]-
	   first  | 1
	   second | one
	   -[ RECORD 2 ]-
	   first  | 2
	   second | two
	   -[ RECORD 3 ]-
	   first  | 3
	   second | three
	   -[ RECORD 4 ]-
	   first  | 4
	   second | four

PostgreSQL 9.2.7			    2014-02-17					  PSQL(1)
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