The SET statement can modify one of the session configuration variables. These can also be queried via SHOW.

Warning:
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 Build an App with CockroachDB tutorials.

Required Privileges

No privileges are required to modify the session settings.

Synopsis

SET SESSION var_name TO = var_value ,
Note:
The SET statement for session settings is unrelated to the other SET TRANSACTION and SET CLUSTER SETTING statements.

Parameters

The SET <session variable> statement accepts two parameters: the variable name and the value to use to modify the variable.

The variable name is case insensitive. The value can be a list of one or more items. For example, the variable search_path is multi-valued.

Supported Variables

Variable name Description Initial value Can be viewed with SHOW?
application_name The current application name for statistics collection. Empty string Yes
database The current database. Database in connection string, or empty if not specified Yes
default_transaction_isolation New in v2.0: The default transaction isolation level for the current session. See Transaction parameters and SET TRANSACTION for more details. Settings in connection string, or "SERIALIZABLE" if not specified 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 SET TRANSACTION for more details. off Yes
sql_safe_updates If true, disallow potentially unsafe SQL statements, including DELETE without a WHERE clause, UPDATE without a WHERE clause, and ALTER TABLE ... DROP COLUMN. See Allow Potentially Unsafe SQL Statements for more details. true for interactive sessions from the built-in SQL client unless --safe-updates=false is specified,
false for sessions from other clients
Yes
search_path Changed in v2.0: A list of schemas that will be searched to resolve unqualified table or function names. For more details, see Name Resolution. "{public}" Yes
server_version_num New in v2.0: The version of PostgreSQL that CockroachDB emulates. Version-dependent Yes
timezone The default 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). Also, DEFAULT, LOCAL, or 0 sets the session time zone to UTC.

See Setting the Time Zone for more details.

Changed in v2.0: This session variable was named "time zone" (with a space) in CockroachDB 1.x. It has been renamed for compatibility with PostgreSQL.
UTC Yes
tracing The trace recording state.

See SET TRACING for more details.
off Yes
transaction_isolation The isolation level of the current transaction. See Transaction parameters for more details.

Changed in v2.0: This session variable was called transaction isolation level (with spaces) in CockroachDB 1.x. It has been renamed for compatibility with PostgreSQL.
SERIALIZABLE Yes
transaction_priority The priority of the current transaction. See Transaction parameters for more details.

Changed in v2.0: This session variable was called transaction priority (with a space) in CockroachDB 1.x. It has been renamed for compatibility with PostgreSQL.
NORMAL Yes
transaction_read_only New in v2.0: The access mode of the current transaction. See Set Transaction for more details. off Yes
transaction_status The state of the current transaction. See Transactions for more details.

Changed in v2.0: This session variable was called transaction status (with a space) in CockroachDB 1.x. It has been renamed for compatibility with PostgreSQL.
NoTxn Yes
client_encoding Ignored; recognized for compatibility with PostgreSQL clients. Only possible value is "UTF8". N/A No
client_min_messages Ignored; recognized for compatibility with PostgreSQL clients. Only possible value is "on". N/A No
extra_float_digits Ignored; recognized for compatibility with PostgreSQL clients. N/A No
standard_conforming_strings Ignored; recognized for compatibility with PostgreSQL clients. N/A No

Special syntax cases:

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 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 demonstrates how SET can be used to configure the default database for the current session:

> SET database = bank;
> SHOW database;
+----------+
| database |
+----------+
| bank     |
+----------+
(1 row)

Set Variables to Values Containing Spaces

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

> SET database = "database name with spaces";
> SHOW database;
+---------------------------+
|         database          |
+---------------------------+
| database name with spaces |
+---------------------------+
(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

Tip:
You can use RESET to reset a session variable as well.
> SET default_transaction_isolation = SNAPSHOT;
> SHOW default_transaction_isolation;
+-------------------------------+
| default_transaction_isolation |
+-------------------------------+
| SNAPSHOT                      |
+-------------------------------+
(1 row)
> SET default_transaction_isolation = DEFAULT;
> SHOW default_transaction_isolation;
+-------------------------------+
| default_transaction_isolation |
+-------------------------------+
| SERIALIZABLE                  |
+-------------------------------+
(1 row)

SET TIME ZONE

Warning:
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 your client's default time zone for the current session with SET TIME ZONE. This will apply a session offset to all TIMESTAMP WITH TIME ZONE values.

Note:
With setting SET TIME ZONE, CockroachDB uses UTC as the default time zone.

Parameters

The time zone value 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). Also, DEFAULT, LOCAL, or 0 sets the session time zone to UTC.

Example: Set the Default Time Zone via SET TIME ZONE

> SET TIME ZONE 'EST'; -- same as SET "timezone" = 'EST'
> SHOW TIME ZONE;
+-----------+
| time zone |
+-----------+
| EST       |
+-----------+
(1 row)
> SET TIME ZONE DEFAULT; -- same as SET "timezone" = DEFAULT
> SHOW TIME ZONE;
+-----------+
| time zone |
+-----------+
| UTC       |
+-----------+
(1 row)

SET TRACING

SET TRACING changes the trace recording state of the current session. A trace recording can be inspected with the SHOW TRACE FOR SESSION 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 SHOW TRACE.
local Trace recording is enabled; only trace messages issued by the local node are collected.

See Also



Yes No