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SET()				 SQL Commands				 SET()



NAME
       SET - change a run-time parameter


SYNOPSIS
       SET [ SESSION | LOCAL ] name { 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 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  SET	 SESSION  is issued within a transaction that is later
       aborted, the effects of the SET command disappear when the  transaction
       is rolled back. (This behavior represents a change from PostgreSQL ver-
       sions prior to 7.3, where the effects of SET would not roll back	 after
       a  later	 error.)  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 transac-
       tion, 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.

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 trans-
	      action will end immediately.

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

       value  New  value  of parameter. Values can be specified as string con-
	      stants, identifiers, numbers, or comma-separated lists of these.
	      DEFAULT  can  be	used to specify resetting the parameter to its
	      default value.

       Besides the configuration parameters documented in  the	documentation,
       there are a few that can only be adjusted using the SET command or that
       have a special 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 0 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
	      specification. 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 (the one that
		     the server's operating system defaults to).

       See the documentation for more information about time zones. Also,  the
       documentation has a list of the recognized names for time zones.

NOTES
       The function set_config provides equivalent functionality. See the doc-
       umentation.

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 Post-
       greSQL extensions.

SEE ALSO
       RESET [reset(7)], SHOW [show(l)]



SQL - Language Statements	  2010-12-14				 SET()