SET {session variable}

The SET can modify one of the session configuration variables. These can also be queried via . By default, session variable values are set for all future sessions to the database; they do not affect the current session.

The SET statement for session variables is unrelated to the other and statements.

In some cases, client drivers can drop and restart the connection to the server. When this happens, any session configurations made with SET statements are lost. It is therefore more reliable to configure the session in the client’s connection string. For examples in different languages, see the tutorials.

Required privileges

To set the role session variable, the current user must be a member of the admin role, or a member of the target role.

All other session variables do not require to modify.

Synopsis

The SET statement can set a session variable for the duration of the current session (SET {variable}/SET SESSION {variable}), or for the duration of a single transaction (SET LOCAL {variable}).

SET SESSION

By default, session variables are set for the duration of the current session. As a result, SET {variable} and SET SESSION {variable} are equivalent.

SET LOCAL

SET LOCAL is compatible with . Executing a , ROLLBACK TO SAVEPOINT, or RELEASE TO SAVEPOINT statement rolls back any variables set by SET LOCAL.

Parameters

Parameter	Description
var\_name	The name of the session variable to set. The variable name is case-insensitive.
var\_value	The value, or list of values, to assign to the session variable.

Supported variables

Variable name	Description	Initial value	Modify with ?	View with ?
application\_name	The current application name for statistics collection.	Empty string, or cockroach for sessions from the .	Yes	Yes
autocommit\_before\_ddl	When the is set to on, any schema change statement that is sent during an will cause the transaction to before executing the schema change.	off	Yes	Yes
bytea\_output	The .	hex	Yes	Yes
client\_min\_messages	The severity level of notices displayed in the . Accepted values include debug5, debug4, debug3, debug2, debug1, log, notice, warning, and error.	notice	Yes	Yes
copy\_from\_atomic\_enabled	If set to on, statements are committed atomically, matching PostgreSQL behavior. If set to off, COPY FROM statements are segmented into batches of 100 rows unless issued within an explicit transaction, matching the CockroachDB behavior in versions prior to v22.2.	on	Yes	Yes
copy\_transaction\_quality\_of\_service	The default quality of service for statements in the current session. The supported options are regular, critical, and background. See .	background	Yes	Yes
cost\_scans\_with\_default\_col\_size	Whether to prevent the optimizer from considering column size when costing plans.	false	Yes	Yes
crdb\_version	The version of CockroachDB.	CockroachDB OSS version	No	Yes
database	The .	Database in connection string, or empty if not specified.	Yes	Yes
	datestyle	The input string format for and values. Accepted values include ISO,MDY, ISO,DMY, and ISO,YMD.	The value set by the sql.defaults.datestyle (ISO,MDY, by default).	Yes	Yes
default\_int\_size	The size, in bytes, of an type.	8	Yes	Yes
default\_text\_search\_config	The dictionary used to normalize tokens and eliminate stop words when calling a without a configuration parameter. See .	english	Yes	Yes
default\_transaction\_isolation	The isolation level at which transactions in the session execute ( or ). See .	SERIALIZABLE	Yes	Yes
default\_transaction\_priority	The default transaction priority for the current session. The supported options are low, normal, and high.	normal	Yes	Yes
default\_transaction\_quality\_of\_service	The default transaction quality of service for the current session. The supported options are regular, critical, and background. See .	regular	Yes	Yes
default\_transaction\_read\_only	The default transaction access mode for the current session. If set to on, only read operations are allowed in transactions in the current session; if set to off, both read and write operations are allowed. See for more details.	off	Yes	Yes
default\_transaction\_use\_follower\_reads	If set to on, all read-only transactions use to allow the transaction to use follower reads. If set to off, read-only transactions will only use follower reads if an AS OF SYSTEM TIME clause is specified in the statement, with an interval of at least 4.8 seconds.	off	Yes	Yes
disable\_changefeed\_replication	When true, will not emit messages for any changes (e.g., INSERT, UPDATE) issued to watched tables during that session.	false	Yes	Yes
disallow\_full\_table\_scans	If set to on, queries on “large” tables with a row count greater than large\_full\_scan\_rows will not use full table or index scans. If no other query plan is possible, queries will return an error message. This setting does not apply to internal queries, which may plan full table or index scans without checking the session variable.	off	Yes	Yes
enable\_auto\_rehoming	When enabled, the of rows in tables are automatically set to the region of the from which any or statements that operate on those rows originate.	off	Yes	Yes
enable\_create\_stats\_using\_extremes	If on, allows manual creation of using the syntax.	on	Yes	Yes
enable\_durable\_locking\_for\_serializable	Indicates whether CockroachDB replicates locks via , allowing locks to be preserved when leases are transferred. Note that replicating FOR UPDATE and FOR SHARE locks will add latency to those statements. This setting only affects SERIALIZABLE transactions and matches the default READ COMMITTED behavior when enabled.	off	Yes	Yes
enable\_experimental\_alter\_column\_type\_general	If on, it is possible to .	off	Yes	Yes
enable\_implicit\_fk\_locking\_for\_serializable	Indicates whether CockroachDB uses to perform checks. To take effect, the enable\_shared\_locking\_for\_serializable setting must also be enabled. This setting only affects SERIALIZABLE transactions and matches the default READ COMMITTED behavior when enabled.	off	Yes	Yes
enable\_implicit\_select\_for\_update	Indicates whether and statements acquire locks using the FOR UPDATE locking mode during their initial row scan, which improves performance for contended workloads. For more information about how FOR UPDATE locking works, see the documentation for .	on	Yes	Yes
enable\_implicit\_transaction\_for\_batch\_statements	Indicates whether multiple statements in a single query (a “batch statement”) will all run in the same implicit transaction, which matches the PostgreSQL wire protocol.	on	Yes	Yes
enable\_insert\_fast\_path	Indicates whether CockroachDB will use a specialized execution operator for inserting into a table. We recommend leaving this setting on.	on	Yes	Yes
enable\_shared\_locking\_for\_serializable	Indicates whether are enabled for SERIALIZABLE transactions. When off, SELECT statements using FOR SHARE are still permitted under SERIALIZABLE isolation, but silently do not lock.	off	Yes	Yes
enable\_super\_regions	When enabled, you can define a super region: a set of on a multi-region cluster such that your will have all of their stored only in regions that are members of the super region.	off	Yes	Yes
enable\_zigzag\_join	Indicates whether the will plan certain queries using a , which searches for the desired intersection by jumping back and forth between the indexes based on the fact that after constraining indexes, they share an ordering.	on	Yes	Yes
enforce\_home\_region	If set to on, queries return an error and in some cases a suggested resolution if they cannot run entirely in their home region. This can occur if a query has no home region (for example, if it reads from different home regions in a ) or a query’s home region differs from the region. Note that only tables with ZONE can be scanned without error when this is enabled. For more information about home regions, see . This feature is in preview. It is subject to change.	off	Yes	Yes
enforce\_home\_region\_follower\_reads\_enabled	If on while the setting is on, allows enforce\_home\_region to perform AS OF SYSTEM TIME to detect and report a query’s , if any. This feature is in preview. It is subject to change.	off	Yes	Yes
expect\_and\_ignore\_not\_visible\_columns\_in\_copy	If on, with no column specifiers will assume that hidden columns are in the copy data, but will ignore them when applying COPY FROM.	off	Yes	Yes
extra\_float\_digits	The number of digits displayed for floating-point values. Only values between -15 and 3 are supported.	0	Yes	Yes
force\_savepoint\_restart	When set to true, allows the statement to accept any name for a savepoint.	off	Yes	Yes
foreign\_key\_cascades\_limit	Limits the number of that run as part of a single query.	10000	Yes	Yes
idle\_in\_session\_timeout	Automatically terminates sessions that idle past the specified threshold. When set to 0, the session will not timeout.	The value set by the sql.defaults.idle\_in\_session\_timeout (0s, by default).	Yes	Yes
idle\_in\_transaction\_session\_timeout	Automatically terminates sessions that are idle in a transaction past the specified threshold. When set to 0, the session will not timeout.	The value set by the sql.defaults.idle\_in\_transaction\_session\_timeout (0s, by default).	Yes	Yes
index\_recommendations\_enabled	If true, display recommendations to create indexes required to eliminate full table scans. For more details, see .	true	Yes	Yes
inject\_retry\_errors\_enabled	If true, any statement executed inside of an explicit transaction (with the exception of statements) will return a transaction retry error. If the client retries the transaction using the special , after the 3rd retry error, the transaction will proceed as normal. Otherwise, the errors will continue until inject\_retry\_errors\_enabled is set to false. For more details, see .	false	Yes	Yes
	intervalstyle	The input string format for values. Accepted values include postgres, iso\_8601, and sql\_standard.	The value set by the sql.defaults.intervalstyle (postgres, by default).	Yes	Yes
is\_superuser	If on or true, the current user is a member of the .	User-dependent	No	Yes
large\_full\_scan\_rows	Determines which tables are considered “large” such that disallow\_full\_table\_scans rejects full table or index scans of “large” tables. The default value is 0, which disallows all full table or index scans.	User-dependent	No	Yes
legacy\_varchar\_typing	New in v24.3.2: If on, type checking and overload resolution for types ignore overloads that cause errors, allowing comparisons between VARCHAR and non-STRING-like placeholder values to execute successfully. If off, type checking of these comparisons is more strict and must be handled with explicit type casts.	on	Yes	Yes
locality	The location of the node. For more information, see .	Node-dependent	No	Yes
lock\_timeout	The amount of time a query can spend acquiring or waiting for a single . In CockroachDB, unlike in PostgreSQL, non-locking reads wait for conflicting locks to be released. As a result, the lock\_timeout configuration applies to writes, and to locking and non-locking reads in read-write and read-only transactions. If lock\_timeout = 0, queries do not timeout due to lock acquisitions.	The value set by the sql.defaults.lock\_timeout (0, by default)	Yes	Yes
multiple\_active\_portals\_enabled	Whether to enable the pgwire feature.	false	Yes	Yes
node\_id	The ID of the node currently connected to. This variable is particularly useful for verifying load balanced connections.	Node-dependent	No	Yes
null\_ordered\_last	Set the default ordering of NULLs. The default order is NULLs first for ascending order and NULLs last for descending order.	false	Yes	Yes
optimizer\_merge\_joins\_enabled	If on, the optimizer will explore query plans with merge joins.	on	Yes	Yes
optimizer\_push\_offset\_into\_index\_join	If on, the optimizer will attempt to push offset expressions into index join expressions to produce more efficient query plans.	on	Yes	Yes
optimizer\_use\_forecasts	If on, the optimizer uses forecasted statistics for query planning.	on	Yes	Yes
optimizer\_use\_histograms	If on, the optimizer uses collected histograms for cardinality estimation.	on	No	Yes
optimizer\_use\_improved\_multi\_column\_selectivity\_estimate	If on, the optimizer uses an improved selectivity estimate for multi-column predicates.	on	Yes	Yes
optimizer\_use\_improved\_zigzag\_join\_costing	If on, the cost of is updated so they will be never be chosen over scans unless they produce fewer rows. To take effect, the enable\_zigzag\_join setting must also be enabled.	on	Yes	Yes
optimizer\_use\_lock\_op\_for\_serializable	If on, the optimizer uses a Lock operator to construct query plans for SELECT statements using the clauses. This setting only affects SERIALIZABLE transactions. READ COMMITTED transactions are evaluated with the Lock operator regardless of the setting.	off	Yes	Yes
optimizer\_use\_merged\_partial\_statistics	If on, the optimizer uses merged with existing full for cardinality estimation.	off	Yes	Yes
optimizer\_use\_multicol\_stats	If on, the optimizer uses collected multi-column statistics for cardinality estimation.	on	No	Yes
optimizer\_use\_not\_visible\_indexes	If on, the optimizer uses not visible indexes for planning.	off	No	Yes
optimizer\_use\_virtual\_computed\_column\_stats	If on, the optimizer uses table statistics on .	on	Yes	Yes
plan\_cache\_mode	The type of plan that is cached in the : auto, force\_generic\_plan, or force\_custom\_plan. For more information, refer to .	force\_custom\_plan	Yes	Yes
plpgsql\_use\_strict\_into	If on, PL/pgSQL behave as though the STRICT option is specified. This causes the SQL statement to error if it does not return exactly one row.	off	Yes	Yes
pg\_trgm.similarity\_threshold	The threshold above which a string comparison returns true. The value must be between 0 and 1. For more information, see .	0.3	Yes	Yes
prefer\_lookup\_joins\_for\_fks	If on, the optimizer prefers to when performing checks.	off	Yes	Yes
reorder\_joins\_limit	Maximum number of joins that the optimizer will attempt to reorder when searching for an optimal query execution plan. For more information, see .	8	Yes	Yes
require\_explicit\_primary\_keys	If on, CockroachDB throws an error for all tables created without an explicit primary key defined.	off	Yes	Yes
search\_path	A list of schemas that will be searched to resolve unqualified table or function names. For more details, see .	public	Yes	Yes
serial\_normalization	Specifies the default handling of in table definitions. Valid options include 'rowid', 'virtual\_sequence', sql\_sequence, sql\_sequence\_cached, , and unordered\_rowid. If set to 'virtual\_sequence', the SERIAL type auto-creates a sequence for better compatibility with Hibernate sequences. If set to sql\_sequence\_cached or sql\_sequence\_cached\_node, you can use the sql.defaults.serial\_sequences\_cache\_size to control the number of values to cache in a user’s session, with a default of 256. If set to unordered\_rowid, the SERIAL type generates a globally unique 64-bit integer (a combination of the insert timestamp and the ID of the node executing the statement) that does not have unique ordering.	'rowid'	Yes	Yes
server\_version	The version of PostgreSQL that CockroachDB emulates.	Version-dependent	No	Yes
server\_version\_num	The version of PostgreSQL that CockroachDB emulates.	Version-dependent	Yes	Yes
session\_id	The ID of the current session.	Session-dependent	No	Yes
session\_user	The user connected for the current session.	User in connection string	No	Yes
sql\_safe\_updates	If true, the following potentially unsafe SQL statements are disallowed: of a non-empty database and all dependent objects; and without a WHERE clause, unless a clause is included; and without a WHERE or clause; ; and converting an existing table to using , unless a has already been added to the table. For more details, refer to .	true for interactive sessions from the , false for sessions from other clients	Yes	Yes
statement\_timeout	The amount of time a statement can run before being stopped. This value can be an int (e.g., 10) and will be interpreted as milliseconds. It can also be an interval or string argument, where the string can be parsed as a valid interval (e.g., '4s'). A value of 0 turns it off.	The value set by the sql.defaults.statement\_timeout (0s, by default).	Yes	Yes
stub\_catalog\_tables	If off, querying an unimplemented, empty table will result in an error, as is the case in v20.2 and earlier. If on, querying an unimplemented, empty pg\_catalog table simply returns no rows.	on	Yes	Yes
	timezone	The default time zone for the current session.	UTC	Yes	Yes
	tracing	The trace recording state.	off	Yes	Yes
transaction\_isolation	The isolation level at which the transaction executes ( or ). See .	SERIALIZABLE	Yes	Yes
transaction\_priority	The priority of the current transaction. See Transactions: Transaction priorities for more details. This session variable was called transaction priority (with a space) in CockroachDB 1.x. It has been renamed for compatibility with PostgreSQL.	NORMAL	Yes	Yes
transaction\_read\_only	The access mode of the current transaction. See for more details.	off	Yes	Yes
transaction\_rows\_read\_err	The limit for the number of rows read by a SQL transaction. If this value is exceeded the transaction will fail (or the event will be logged to SQL\_INTERNAL\_PERF for internal transactions).	0	Yes	Yes
transaction\_rows\_read\_log	The threshold for the number of rows read by a SQL transaction. If this value is exceeded, the event will be logged to SQL\_PERF (or SQL\_INTERNAL\_PERF for internal transactions).	0	Yes	Yes
transaction\_rows\_written\_err	The limit for the number of rows written by a SQL transaction. If this value is exceeded the transaction will fail (or the event will be logged to SQL\_INTERNAL\_PERF for internal transactions).	0	Yes	Yes
transaction\_rows\_written\_log	The threshold for the number of rows written by a SQL transaction. If this value is exceeded, the event will be logged to SQL\_PERF (or SQL\_INTERNAL\_PERF for internal transactions).	0	Yes	Yes
transaction\_status	The state of the current transaction. See for more details.	NoTxn	No	Yes
transaction\_timeout	Aborts an explicit when it runs longer than the configured duration. Stored in milliseconds; can be expressed in milliseconds or as an .	0	Yes	Yes
troubleshooting\_mode\_enabled	When enabled, avoid performing additional work on queries, such as collecting and emitting telemetry data. This session variable is particularly useful when the cluster is experiencing issues, unavailability, or failure.	off	Yes	Yes
use\_declarative\_schema\_changer	Whether to use the declarative schema changer for supported statements.	on	Yes	Yes
	vectorize	The vectorized execution engine mode. Options include on and off. For more details, see .	on	Yes	Yes
virtual\_cluster\_name	The name of the virtual cluster that the SQL client is connected to.	Session-dependent	No	Yes

The following session variables are exposed only for backwards compatibility with earlier CockroachDB releases and have no impact on how CockroachDB runs:

Variable name	Initial value	Modify with ?	View with ?
backslash\_quote	safe\_encoding	No	Yes
client\_encoding	UTF8	No	Yes
default\_tablespace		No	Yes
enable\_drop\_enum\_value	off	Yes	Yes
enable\_seqscan	on	Yes	Yes
escape\_string\_warning	on	No	Yes
experimental\_enable\_hash\_sharded\_indexes	off	Yes	Yes
integer\_datetimes	on	No	Yes
max\_identifier\_length	128	No	Yes
max\_index\_keys	32	No	Yes
row\_security	off	No	Yes
standard\_conforming\_strings	on	No	Yes
server\_encoding	UTF8	Yes	Yes
synchronize\_seqscans	on	No	Yes
synchronous\_commit	on	Yes	Yes

Special syntax cases

CockroachDB supports the following syntax cases, for compatibility with common SQL syntax patterns:

Syntax	Equivalent to	Notes
USE ...	SET database = ...	This is provided as convenience for users with a MySQL/MSSQL background.
SET NAMES ...	SET client\_encoding = ...	This is provided for compatibility with PostgreSQL clients.
SET ROLE	SET role =	This is provided for compatibility with PostgreSQL clients.
RESET ROLE	SET role = 'none'/SET role = current\_user()	This is provided for compatibility with PostgreSQL clients.
SET SCHEMA	SET search\_path =	This is provided for better compatibility with PostgreSQL.
SET SESSION CHARACTERISTICS AS TRANSACTION ISOLATION LEVEL ...	SET default\_transaction\_isolation = ...	This is provided for compatibility with standard SQL.
SET TIME ZONE ...	SET timezone = ...	This is provided for compatibility with PostgreSQL clients.

Examples

Set simple variables

The following examples demonstrate how to use SET to configure the default database for the current session:

SET application_name = movr_app;

SHOW application_name;

  application_name
--------------------
  movr_app
(1 row)

Set variables to values containing spaces

The following demonstrates how to use quoting to use values containing spaces:

SET application_name = "movr app";

SHOW application_name;

  application_name
--------------------
  movr app
(1 row)

Set variables to a list of values

The following demonstrates how to assign a list of values:

SET search_path = pg_catalog,public;

SHOW search_path;

     search_path
----------------------
  pg_catalog, public
(1 row)

Reset a variable to its default value

You can use to reset a session variable as well.

SHOW search_path;

     search_path
----------------------
  pg_catalog, public
(1 row)

SET search_path = DEFAULT;

SHOW search_path;

    search_path
-------------------
  "$user", public
(1 row)

Set a variable for the duration of a single transaction

To set a variable for the duration of a single transaction, use the SET LOCAL statement.

SHOW application_name;

  application_name
--------------------
  movr app
(1 row)

BEGIN;
SET LOCAL application_name = demo;
SHOW application_name;

  application_name
--------------------
  demo
(1 row)

COMMIT;
SHOW application_name;

  application_name
--------------------
  movr app
(1 row)

Roll back session variables set for a transaction

You can roll back session variable settings to .

SHOW timezone;

  timezone
------------
  UTC
(1 row)

BEGIN;
SET timezone = '+3';
SAVEPOINT s1;
SHOW timezone;

  timezone
------------
  +3
(1 row)

SET LOCAL timezone = '+1';
SHOW timezone;

  timezone
------------
  +1
(1 row)

ROLLBACK TO SAVEPOINT s1;
SHOW timezone;

  timezone
------------
  +3
(1 row)

COMMIT;
SHOW timezone;

  timezone
------------
  +3
(1 row)

Assume another role

To assume another for the duration of a session, use SET ROLE <role>. SET ROLE <role> is equivalent to SET role = <role>.

To assume a new role, the current user must be a member of the admin role, or a member of the target role.

SHOW role;

  role
--------
  root
(1 row)

CREATE ROLE new_role;
SHOW ROLES;

  username | options | member_of
-----------+---------+------------
  admin    |         | {}
  new_role | NOLOGIN | {}
  root     |         | {admin}
(3 rows)

SET ROLE new_role;
SHOW role;

    role
------------
  new_role
(1 row)

To reset the role of the current user, use a statement. RESET ROLE is equivalent to SET role = 'none' and SET role = current_user().

RESET ROLE;
SHOW role;

  role
--------
  root
(1 row)

To assume a role for the duration of a single transaction, use SET LOCAL ROLE.

BEGIN;
SET LOCAL ROLE new_role;
SHOW role;

    role
------------
  new_role
(1 row)

COMMIT;
SHOW role;

  role
--------
  root
(1 row)

SET TIME ZONE

As a best practice, we recommend not using this setting and avoid setting a session time for your database. We instead recommend converting UTC values to the appropriate time zone on the client side.

You can control the default time zone for a session with SET TIME ZONE. This will apply an offset to all and values in the session. By default, CockroachDB uses UTC as the time zone for SET TIME ZONE offsets.

Parameters

The input passed to SET TIME ZONE indicates the time zone for the current session. This value can be a string representation of a local system-defined time zone (e.g., 'EST', 'America/New_York') or a positive or negative numeric offset from UTC (e.g., -7, +7, or UTC-7, UTC+7) or GMT (e.g., GMT-7, GMT+7). The numeric offset input can also be colon-delimited (e.g., -7:00, GMT+7:00).

When setting a time zone, note the following:

• Timezone abbreviations are case-insensitive.
• To see a list of supported timezones, their nicknames, and their offsets, run the following query:

  SELECT * FROM pg_timezone_names;

• DEFAULT, LOCAL, or 0 sets the session time zone to UTC.
• Only offsets specified by integers (e.g., -7, 7) use the ISO 8601 time offset (i.e., the offset input is parsed as hours east of UTC). If you explicitly specify UTC or GMT for the time zone offset (e.g., UTC-7,GMT+7), or if the numeric input is colon-delimited (e.g., -7:00, GMT+7:00), CockroachDB uses the POSIX time offset instead (i.e., hours west of the specified time zone). This means that specifying an offset of -7 (i.e., -7 east of UTC) is equivalent to specifying GMT+7 (i.e., 7 west of UTC).

Example: Set the default time zone via SET TIME ZONE

> SET TIME ZONE 'EST'; -- same as SET "timezone" = 'EST'

> SHOW TIME ZONE;

  timezone
+----------+
  EST
(1 row)

> SET TIME ZONE DEFAULT; -- same as SET "timezone" = DEFAULT

> SHOW TIME ZONE;

  timezone
+----------+
  UTC
(1 row)

SET TRACING

SET TRACING changes the trace recording state of the current session. A trace recording can be inspected with the statement.

Value	Description
off	Trace recording is disabled.
cluster	Trace recording is enabled; distributed traces are collected.
on	Same as cluster.
kv	Same as cluster except that “kv messages” are collected instead of regular trace messages. See .
results	Result rows and row counts are copied to the session trace. This must be specified in order for the output of a query to be printed in the session trace. Example: SET tracing = kv, results;

Considerations

Session variable precedence

When a starts, CockroachDB determines the initial value of each by evaluating the settings in the following order (items earlier in the list take precedence over later items):

1. : A value supplied as a query parameter in the connection URL (for example, .../movr?sslmode=disable&timezone=UTC ).
2. : A value set by ALTER ROLE {role_name} IN DATABASE {db_name} SET {var}={value}.
3. : A value set by ALTER ROLE {role_name} SET {var}={value}.
4. : A value set by ALTER ROLE ALL IN DATABASE {db_name} SET {var}={value} or equivalently by ALTER DATABASE {db_name} SET {var}={value}.
5. : A value set by ALTER ROLE ALL SET {var}={value}.

If a session variable is not modified using any of the preceding methods, the built-in system default value is used. Note that the is exempt from settings 3–5. The root user is only affected by values specified in the connection string.

You can also set session variables for the duration of a single transaction by using .

Changes to defaults using the preceding methods only apply to future sessions. This is because session variable resolution happens at session start time. To change a default value in an existing open session, set the variable explicitly with .

Known Limitations

SET does not properly apply within a transaction. For example, in the following transaction, showing the TIME ZONE does not return 2 as expected after the rollback:

SET TIME ZONE +2;
BEGIN;
SET TIME ZONE +3;
ROLLBACK;
SHOW TIME ZONE;

timezone
------------
3

See also