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       SET - change a run-time parameter


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


       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.


              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.

              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
              specification. Here are examples of valid values:

                     The time zone for Berkeley, California.

                     The time zone for Italy.

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

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


                     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.


       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.


       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 the time zone for Italy:

       SET TIME ZONE ’Europe/Rome’;


       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.


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