SET(7)								   SQL Commands 							    SET(7)

NAME

       SET - change a run-time parameter

SYNOPSIS

       SET [ SESSION | LOCAL ] configuration_parameter { TO | = } { value | 'value' | DEFAULT }
       SET [ SESSION | LOCAL ] TIME ZONE { timezone | LOCAL | DEFAULT }

DESCRIPTION

       The  SET  command  changes run-time configuration parameters. Many of the run-time parameters listed in in the documentation can be changed
       on-the-fly with SET.  (But some require superuser privileges to change, and others cannot be changed after server or session  start.)   SET
       only affects the value used by the current session.

       If  SET	(or  equivalently SET SESSION) is issued within a transaction that is later aborted, the effects of the SET command disappear when
       the transaction is rolled back. Once the surrounding transaction is committed, the effects will persist	until  the  end  of  the  session,
       unless overridden by another SET.

       The effects of SET LOCAL last only till the end of the current transaction, whether committed or not. A special case is SET followed by SET
       LOCAL within a single transaction: the SET LOCAL value will be seen until the end of the transaction, but afterwards (if the transaction is
       committed) the SET value will take effect.

       The effects of SET or SET LOCAL are also canceled by rolling back to a savepoint that is earlier than the command.

       If  SET LOCAL is used within a function that has a SET option for the same variable (see CREATE FUNCTION [create_function(7)]), the effects
       of the SET LOCAL command disappear at function exit; that is, the value in effect when the function was called  is  restored  anyway.  This
       allows  SET  LOCAL to be used for dynamic or repeated changes of a parameter within a function, while still having the convenience of using
       the SET option to save and restore the caller's value. However, a regular SET command overrides any surrounding function's SET option;  its
       effects will persist unless rolled back.

	      Note:  In PostgreSQL versions 8.0 through 8.2, the effects of a SET LOCAL would be canceled by releasing an earlier savepoint, or by
	      successful exit from a PL/pgSQL exception block. This behavior has been changed because it was deemed unintuitive.

PARAMETERS

       SESSION
	      Specifies that the command takes effect for the current session.	(This is the default if neither SESSION nor LOCAL appears.)

       LOCAL  Specifies that the command takes effect for only the current transaction. After COMMIT or ROLLBACK, the session-level setting  takes
	      effect  again. Note that SET LOCAL will appear to have no effect if it is executed outside a BEGIN block, since the transaction will
	      end immediately.

       configuration_parameter
	      Name of a settable run-time parameter. Available parameters are documented in in the documentation and below.

       value  New value of parameter. Values can be specified as string constants, identifiers, numbers, or comma-separated  lists  of	these,	as
	      appropriate  for the particular parameter.  DEFAULT can be written to specify resetting the parameter to its default value (that is,
	      whatever value it would have had if no SET had been executed in the current session).

       Besides the configuration parameters documented in in the documentation, there are a few that can only be adjusted using the SET command or
       that have a special syntax:

       SCHEMA SET SCHEMA 'value' is an alias for SET search_path TO value. Only one schema can be specified using this syntax.

       NAMES  SET NAMES value is an alias for SET client_encoding TO value.

       SEED   Sets  the  internal seed for the random number generator (the function random). Allowed values are floating-point numbers between -1
	      and 1, which are then multiplied by 231-1.

	      The seed can also be set by invoking the function setseed:

	      SELECT setseed(value);

       TIME ZONE
	      SET TIME ZONE value is an alias for SET timezone TO value. The syntax SET TIME ZONE allows special syntax for the time zone specifi-
	      cation. Here are examples of valid values:

	      'PST8PDT'
		     The time zone for Berkeley, California.

	      'Europe/Rome'
		     The time zone for Italy.

	      -7     The time zone 7 hours west from UTC (equivalent to PDT). Positive values are east from UTC.

	      INTERVAL '-08:00' HOUR TO MINUTE
		     The time zone 8 hours west from UTC (equivalent to PST).

	      LOCAL

	      DEFAULT
		     Set  the  time zone to your local time zone (that is, the server's default value of timezone; if this has not been explicitly
		     set anywhere, it will be the zone that the server's operating system defaults to).

       See in the documentation for more information about time zones.

NOTES

       The function set_config provides equivalent functionality; see in the documentation.  Also, it is possible to UPDATE the pg_settings system
       view to perform the equivalent of SET.

EXAMPLES

       Set the schema search path:

       SET search_path TO my_schema, public;

       Set the style of date to traditional POSTGRES with ``day before month'' input convention:

       SET datestyle TO postgres, dmy;

       Set the time zone for Berkeley, California:

       SET TIME ZONE 'PST8PDT';

       Set the time zone for Italy:

       SET TIME ZONE 'Europe/Rome';

COMPATIBILITY

       SET  TIME  ZONE extends syntax defined in the SQL standard. The standard allows only numeric time zone offsets while PostgreSQL allows more
       flexible time-zone specifications. All other SET features are PostgreSQL extensions.

SEE ALSO

       RESET [reset(7)], SHOW [show(7)]

SQL - Language Statements					    2010-05-14								    SET(7)