1SET(7) SQL Commands SET(7)
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6 SET - change a run-time parameter
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10 SET [ SESSION | LOCAL ] configuration_parameter { TO | = } { value | 'value' | DEFAULT }
11 SET [ SESSION | LOCAL ] TIME ZONE { timezone | LOCAL | DEFAULT }
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15 The SET command changes run-time configuration parameters. Many of the
16 run-time parameters listed in in the documentation can be changed on-
17 the-fly with SET. (But some require superuser privileges to change,
18 and others cannot be changed after server or session start.) SET only
19 affects the value used by the current session.
20 If SET (or equivalently SET SESSION) is issued within a transaction
22 that is later aborted, the effects of the SET command disappear when
23 the transaction is rolled back. Once the surrounding transaction is
24 committed, the effects will persist until the end of the session,
25 unless overridden by another SET.
26 The effects of SET LOCAL last only till the end of the current transac‐
28 tion, whether committed or not. A special case is SET followed by SET
29 LOCAL within a single transaction: the SET LOCAL value will be seen
30 until the end of the transaction, but afterwards (if the transaction is
31 committed) the SET value will take effect.
32 The effects of SET or SET LOCAL are also canceled by rolling back to a
34 savepoint that is earlier than the command.
35 If SET LOCAL is used within a function that has a SET option for the
37 same variable (see CREATE FUNCTION [create_function(7)]), the effects
38 of the SET LOCAL command disappear at function exit; that is, the value
39 in effect when the function was called is restored anyway. This allows
40 SET LOCAL to be used for dynamic or repeated changes of a parameter
41 within a function, while still having the convenience of using the SET
42 option to save and restore the caller's value. However, a regular SET
43 command overrides any surrounding function's SET option; its effects
44 will persist unless rolled back.
45 Note: In PostgreSQL versions 8.0 through 8.2, the effects of a
47 SET LOCAL would be canceled by releasing an earlier savepoint,
48 or by successful exit from a PL/pgSQL exception block. This
49 behavior has been changed because it was deemed unintuitive.
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53 SESSION
54 Specifies that the command takes effect for the current session.
55 (This is the default if neither SESSION nor LOCAL appears.)
56 LOCAL Specifies that the command takes effect for only the current
58 transaction. After COMMIT or ROLLBACK, the session-level setting
59 takes effect again. Note that SET LOCAL will appear to have no
60 effect if it is executed outside a BEGIN block, since the trans‐
61 action will end immediately.
62 configuration_parameter
64 Name of a settable run-time parameter. Available parameters are
65 documented in in the documentation and below.
66 value New value of parameter. Values can be specified as string con‐
68 stants, identifiers, numbers, or comma-separated lists of these,
69 as appropriate for the particular parameter. DEFAULT can be
70 written to specify resetting the parameter to its default value
71 (that is, whatever value it would have had if no SET had been
72 executed in the current session).
73 Besides the configuration parameters documented in in the documenta‐
75 tion, there are a few that can only be adjusted using the SET command
76 or that have a special syntax:
77 SCHEMA SET SCHEMA 'value' is an alias for SET search_path TO value.
79 Only one schema can be specified using this syntax.
80 NAMES SET NAMES value is an alias for SET client_encoding TO value.
82 SEED Sets the internal seed for the random number generator (the
84 function random). Allowed values are floating-point numbers
85 between -1 and 1, which are then multiplied by 231-1.
86 The seed can also be set by invoking the function setseed:
88 SELECT setseed(value);
90 TIME ZONE
93 SET TIME ZONE value is an alias for SET timezone TO value. The
94 syntax SET TIME ZONE allows special syntax for the time zone
95 specification. Here are examples of valid values:
96 'PST8PDT'
98 The time zone for Berkeley, California.
99 'Europe/Rome'
101 The time zone for Italy.
102 -7 The time zone 7 hours west from UTC (equivalent to PDT).
104 Positive values are east from UTC.
105 INTERVAL '-08:00' HOUR TO MINUTE
107 The time zone 8 hours west from UTC (equivalent to PST).
108 LOCAL
110 DEFAULT
112 Set the time zone to your local time zone (that is, the
113 server's default value of timezone; if this has not been
114 explicitly set anywhere, it will be the zone that the
115 server's operating system defaults to).
116 See in the documentation for more information about time zones.
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120 The function set_config provides equivalent functionality; see in the
121 documentation. Also, it is possible to UPDATE the pg_settings system
122 view to perform the equivalent of SET.
123
125 Set the schema search path:
126 SET search_path TO my_schema, public;
128 Set the style of date to traditional POSTGRES with ``day before month''
131 input convention:
132 SET datestyle TO postgres, dmy;
134 Set the time zone for Berkeley, California:
137 SET TIME ZONE 'PST8PDT';
139 Set the time zone for Italy:
142 SET TIME ZONE 'Europe/Rome';
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147 SET TIME ZONE extends syntax defined in the SQL standard. The standard
148 allows only numeric time zone offsets while PostgreSQL allows more
149 flexible time-zone specifications. All other SET features are Post‐
150 greSQL extensions.
151
153 RESET [reset(7)], SHOW [show(7)]
154SQL - Language Statements 2011-09-22 SET(7)