SET
Description
The command changes server configuration parameters. Any configuration parameter classified as a session parameter can be changed on-the-fly with SET
. SET
affects only 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. 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.
If SET LOCAL
is used within a function that includes a option for the same configuration parameter (see CREATE FUNCTION), the effects of the SET LOCAL
command disappear at function exit; 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 retaining the convenience of using the SET
option to save and restore the caller’s value. Note that a regular SET
command overrides any surrounding function’s SET
option; its effects persist unless rolled back.
If you create a cursor with the DECLARE
command in a transaction, you cannot use the SET
command in the transaction until you close the cursor with the CLOSE
command.
See for information about server parameters.
SESSION
Specifies that the command takes effect for the current session. This is the default.
LOCAL
configuration_parameter
The name of a Greenplum Database configuration parameter. Only parameters classified as session can be changed with SET
. See for details.
value
New value of parameter. Values can be specified as string constants, identifiers, numbers, or comma-separated lists of these. can be used to specify resetting the parameter to its default value. If specifying memory sizing or time units, enclose the value in single quotes.
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'
'Europe/Rome'
-7
(time zone 7 hours west from UTC)
LOCAL
DEFAULT
Set the time zone to your local time zone (the one that the server’s operating system defaults to). See the Time zone section of the PostgreSQL documentation for more information about time zones in Greenplum Database.
Examples
Set the schema search path:
SET search_path TO my_schema, public;
Increase the segment host memory per query to 200 MB:
Set the style of date to traditional POSTGRES with “day before month” input convention:
SET datestyle TO postgres, dmy;
Set the time zone for San Mateo, California (Pacific Time):
Set the time zone for Italy:
SET TIME ZONE
extends syntax defined in the SQL standard. The standard allows only numeric time zone offsets while Greenplum Database allows more flexible time-zone specifications. All other SET
features are Greenplum Database extensions.
See Also
Parent topic: SQL Command Reference