told about those parameters via command line options, namely ,
, , and respectively.
If an argument is found that does not belong to any option it will be interpreted
- as database name as well. Not all these options are required, defaults do apply.
- If you omit the host name psql will connect via domain sockets to a server on the
+ as the database name (or the user name, if the database name is also
+ given). Not all these options are required, defaults do apply.
+ If you omit the host name psql will connect via a UNIX domain socket
+ to a server on the
local host. The default port number is compile-time determined. Since the database
- server uses the same default, chances are you don't have to specify the port in most
- settings. The default user name is your Unix username, the same with 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 username, as is the default
+ database name.
Note that you can't just connect to any database under any username. Your database
administrator should have informed you about your access rights. To save you some typing
you can also set the environment variables PGDATABASE,
- PGHOST, PGPORT, PGUSER,
- respectively to appropriate values.
+ PGHOST, PGPORT and PGUSER
+ to appropriate values.
In normal operation,
psql provides a prompt with
- the name of the database t
hat psql is currently
- connected to followed by the string "=>". For example,
+ the name of the database t
o which psql is currently
+ connected, followed by the string "=>". For example,
$ psql testdb
Welcome to psql, the PostgreSQL interactive terminal.
At the prompt, the user may type in
SQL queries.
Ordinarily, input lines are sent to the backend when a query-terminating
semicolon is reached. An end of line does not terminate a query! Thus queries
- can be spread over serveral lines for clarity. If the query was sent and without
+ can be spread over several lines for clarity. If the query was sent and without
error, the query results are displayed on the screen.
Anything you enter in
psql that begins with an
unquoted backslash is a
psql meta-command that is
- processe
s by
psql itself.
+ processe
d by
psql itself.
These commands are what makes
psql interesting for administration or scripting.
Meta-commands are more commonly called slash or backslash commands.
To include whitespace into an argument you must quote it with a single
- quote. To include a single quote into such an argument, preceed it by
+ quote. To include a single quote into such an argument, precede it by
a backslash. Anything contained in single quotes is furthermore subject to
C-like substitutions for \n (new line), \t
(tab), \digits,
Performs a frontend (client) copy. This is an operation that runs an
- but instead of the backend reading or writing the specified file, and
+ but instead of the backend's reading or writing the specified file, and
consequently requiring backend access and special user privilege,
as well as being bound to the file system accessible by the backend,
- file and routes the data to or from the backend onto the local file system.
+ file and routes the data between the backend and the local file system.
- The syntax of the command is
in analogy to the
SQL- COPY command, see its description for the details.
- Note that because of this, special parsing rules apply to the
+ The syntax of the command is
similar to that of the
SQL+ COPY command (see its description for the details).
+ 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.
Note the difference in interpretation of stdin and stdout
- between frontend and backend copies: In a frontend copy these always refer
+ between frontend and backend copies: in a frontend copy these always refer
to
psql's input and output stream. On a backend
- copy stdin comes from whereever the COPY
- itself came from (for example, a script ran with the ) option,
+ copy stdin comes from wherever the COPY
+ itself came from (for example, a script run with the option),
and stdout refers to the query output stream (see
\o meta-command below).
If filename is specified,
- the file is edited and after the editor exit its content is copied
+ the file is edited; after the editor exits, its content is copied
back to the query buffer. If no argument is given, the current query
buffer is copied to a temporary file which is then edited in the same
fashion.
- Expanded mode is support by all four output modes.
+ Expanded mode is supported by all four output modes.
tableattr (or T) [ text ]
- Allows you to specify any attributes to be place
s inside the
HTML+ Allows you to specify any attributes to be place
d inside the
HTML table tag. This could for example be
cellpadding or bgcolor. Note that you
probably don't want to specify border here, as
As of
psql version 7.0 it is no longer
- necessary, in fact, to save the command history as that will be done
- automatically on program termination. The history is then
- also
automatically loaded every time
psql+ necessary to save the command history, since that will be done
+ automatically on program termination. The history is
+ also
loaded automatically every time
psql starts up.
Sets the internal variable name
to value or, if more than one
value is given, to the concatenation of all of them. If no second argument
- is given, the variable is just set with not value. To unset a variable, use
+ is given, the variable is just set with no value. To unset a variable, use
the \unset command.
- Although you are welcome to set any variable to anything you want to,
-
psql treats several variables special.
+ 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.
that is completely parseable by the backend (i.e., it contains no
psql specific features), or it is a single backslash command. Thus
you cannot mix
SQL and
psql- meta-commands. To achieve this you could pipe the string into
+ meta-commands. To achieve that, you could pipe the string into
echo "\x \\ select * from foo;" | psql.
-E, --echo-hidden
- Echos the actual queries generated by \d and other backslash commands.
+ Echoes the actual queries generated by \d and other backslash commands.
You can use this if you wish to include similar functionality into
your own programs. This is equivalent to setting the variable
ECHO_HIDDEN from within
psql.
-S, --single-line
- Runs in single-line mode where a newline terminates a query, like a semicolon would do.
+ Runs in single-line mode where a newline terminates a query, as a semicolon does.
This mode is provided for those who insist on it, but you are not necessarily
encouraged to use it. In particular, if you mix
SQL and
meta-commands on a line the order of execution might not always be clear to
- the unexperienced user.
+ the inexperienced user.
Turn off printing of column names and result row count footers, etc.
- It is completely equivalent to the \t.
+ It is completely equivalent to the \t 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. These assignments are done
during a very early state of startup, so variables reserved for internal purposes
- might get overwritten again.
+ might get overwritten later.
interface to specially store data that does not fit into one tuple,
all the operations must be contained in a transaction block. (See the
documentation of the large object interface for more information.) Since
-
psql has no way to
keep track if you already
+
psql has no way to
tell if you already
have a transaction in progress when you call one of its internal
commands \lo_export, \lo_import,
\lo_unlink it must take some arbitrary action. This
action could either be to roll back any transaction that might already
be in progress, or to commit any such transaction, or to do nothing at
- all. In the latter case you must provide you own
+ all. In the last case you must provide your own
BEGIN TRANSACTION/COMMIT block or
the results will be unpredictable (usually resulting in the desired
- action not being performed in any case).
+ action's not being performed in any case).
By default, if non-interactive scripts encounter an error, such as a
malformed
SQL query or internal meta-command,
- processing continues. This is has been the traditional behaviour of
+ processing continues. This has been the traditional behaviour of
psql but it is sometimes not desirable. If this variable
is set, script processing will immediately terminate. If the script was
called from another script it will terminate in the same fashion.
PORT
- The database server port you are currently connected to. This is set everytime
+ The database server port to which you are currently connected. This is set every time
you connect to a database (including program startup), but can be unset.
SINGLELINE
- This variable is set be the command line options . You
+ This variable is set by the command line option . You
can unset or reset it at run time.
USER
- The database user you are currently connected as. This is set everytime
+ The database user you are currently connected as. This is set every time
you connect to a database (including program startup), but can be unset.
%m
-
The hostname of the database server truncated after the+
The hostname of the database server, truncated after the first dot.
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