SET

Changes the value of a HAWQ configuration parameter.

Synopsis

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

Description

The SET command changes server configuration parameters. Any configuration parameter classified as a session parameter can be changed on-the-fly with SET. See About Server Configuration Parameters. 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. 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 only last 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.

Parameters

SESSION
Specifies that the command takes effect for the current session. This is the default.

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 of a transaction.

configuration_parameter
The name of a HAWQ configuration parameter. Only parameters classified as session can be changed with SET. See About Server Configuration Parameters.

value
New value of parameter. Values can be specified as string constants, identifiers, numbers, or comma-separated lists of these. DEFAULT 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)

INTERVAL '-08:00' HOUR TO MINUTE (time zone 8 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).

Examples

Set the schema search path:

SET search_path TO my_schema, public;

Increase work memory to 200 MB:

SET work_mem TO '200MB';

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 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 HAWQ allows more flexible time-zone specifications. All other SET features are HAWQ extensions.

See Also

RESET, SHOW