1SET(7) PostgreSQL 13.4 Documentation SET(7)
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6 SET - change a run-time parameter
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9 SET [ SESSION | LOCAL ] configuration_parameter { TO | = } { value | 'value' | DEFAULT }
10 SET [ SESSION | LOCAL ] TIME ZONE { timezone | LOCAL | DEFAULT }
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13 The SET command changes run-time configuration parameters. Many of the
14 run-time parameters listed in Chapter 19 can be changed on-the-fly with
15 SET. (But some require superuser privileges to change, and others
16 cannot be changed after server or session start.) SET only affects the
17 value used by the current session.
18 If SET (or equivalently SET SESSION) is issued within a transaction
20 that is later aborted, the effects of the SET command disappear when
21 the transaction is rolled back. Once the surrounding transaction is
22 committed, the effects will persist until the end of the session,
23 unless overridden by another SET.
24 The effects of SET LOCAL last only till the end of the current
26 transaction, whether committed or not. A special case is SET followed
27 by SET LOCAL within a single transaction: the SET LOCAL value will be
28 seen until the end of the transaction, but afterwards (if the
29 transaction is committed) the SET value will take effect.
30 The effects of SET or SET LOCAL are also canceled by rolling back to a
32 savepoint that is earlier than the command.
33 If SET LOCAL is used within a function that has a SET option for the
35 same variable (see CREATE FUNCTION (CREATE_FUNCTION(7))), the effects
36 of the SET LOCAL command disappear at function exit; that is, the value
37 in effect when the function was called is restored anyway. This allows
38 SET LOCAL to be used for dynamic or repeated changes of a parameter
39 within a function, while still having the convenience of using the SET
40 option to save and restore the caller's value. However, a regular SET
41 command overrides any surrounding function's SET option; its effects
42 will persist unless rolled back.
43 Note
45 In PostgreSQL versions 8.0 through 8.2, the effects of a SET LOCAL
46 would be canceled by releasing an earlier savepoint, or by
47 successful exit from a PL/pgSQL exception block. This behavior has
48 been changed because it was deemed unintuitive.
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51 SESSION
52 Specifies that the command takes effect for the current session.
53 (This is the default if neither SESSION nor LOCAL appears.)
54 LOCAL
56 Specifies that the command takes effect for only the current
57 transaction. After COMMIT or ROLLBACK, the session-level setting
58 takes effect again. Issuing this outside of a transaction block
59 emits a warning and otherwise has no effect.
60 configuration_parameter
62 Name of a settable run-time parameter. Available parameters are
63 documented in Chapter 19 and below.
64 value
66 New value of parameter. Values can be specified as string
67 constants, identifiers, numbers, or comma-separated lists of these,
68 as appropriate for the particular parameter. DEFAULT can be
69 written to specify resetting the parameter to its default value
70 (that is, whatever value it would have had if no SET had been
71 executed in the current session).
72 Besides the configuration parameters documented in Chapter 19, there
74 are a few that can only be adjusted using the SET command or that have
75 a special syntax:
76 SCHEMA
78 SET SCHEMA 'value' is an alias for SET search_path TO value. Only
79 one schema can be specified using this syntax.
80 NAMES
82 SET NAMES value is an alias for SET client_encoding TO value.
83 SEED
85 Sets the internal seed for the random number generator (the
86 function random). Allowed values are floating-point numbers between
87 -1 and 1, which are then multiplied by 2^31-1.
88 The seed can also be set by invoking the function setseed:
90 SELECT setseed(value);
92 TIME ZONE
94 SET TIME ZONE value is an alias for SET timezone TO value. The
95 syntax SET TIME ZONE allows special syntax for the time zone
96 specification. Here are examples of valid values:
97 'PST8PDT'
99 The time zone for Berkeley, California.
100 'Europe/Rome'
102 The time zone for Italy.
103 -7
105 The time zone 7 hours west from UTC (equivalent to PDT).
106 Positive values are east from UTC.
107 INTERVAL '-08:00' HOUR TO MINUTE
109 The time zone 8 hours west from UTC (equivalent to PST).
110 LOCAL
112 DEFAULT
113 Set the time zone to your local time zone (that is, the
114 server's default value of timezone).
115 Timezone settings given as numbers or intervals are internally
117 translated to POSIX timezone syntax. For example, after SET TIME
118 ZONE -7, SHOW TIME ZONE would report <-07>+07.
119 See Section 8.5.3 for more information about time zones.
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123 The function set_config provides equivalent functionality; see
124 Section 9.27.1. Also, it is possible to UPDATE the pg_settings system
125 view to perform the equivalent of SET.
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128 Set the schema search path:
129 SET search_path TO my_schema, public;
131 Set the style of date to traditional POSTGRES with “day before month”
133 input convention:
134 SET datestyle TO postgres, dmy;
136 Set the time zone for Berkeley, California:
138 SET TIME ZONE 'PST8PDT';
140 Set the time zone for Italy:
142 SET TIME ZONE 'Europe/Rome';
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146 SET TIME ZONE extends syntax defined in the SQL standard. The standard
147 allows only numeric time zone offsets while PostgreSQL allows more
148 flexible time-zone specifications. All other SET features are
149 PostgreSQL extensions.
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152 RESET(7), SHOW(7)
153PostgreSQL 13.4 2021 SET(7)