SET

SET modifies the value of a configuration parameter for the current session. By default, values are set for the duration of the current session.

To see the current value of a configuration parameter, use SHOW.

Syntax

Field	Use
name	The name of the configuration parameter to modify.
value	The value to assign to the parameter.
SESSION	*(Default)* Set the value for the duration of the current session.
LOCAL	Set the value for the duration of a single transaction.
DEFAULT	Use the parameter’s default value. Equivalent to `RESET`.

Key configuration parameters

Name	Default value	Description	Modifiable?
`cluster`	`quickstart`	The current cluster.	Yes
`cluster_replica`		The target cluster replica for `SELECT` queries.	Yes
`database`	`materialize`	The current database.	Yes
`search_path`	`public`	The schema search order for names that are not schema-qualified.	Yes
`transaction_isolation`	`strict serializable`	The transaction isolation level. For more information, see Consistency guarantees. Accepts values: `serializable`, `strict serializable`.	Yes

Other configuration parameters

Name	Default value	Description	Modifiable?
`allowed_cluster_replica_sizes`	Varies	The allowed sizes when creating a new cluster replica.	Contact support
`application_name`		The application name to be reported in statistics and logs. This parameter is typically set by an application upon connection to Materialize (e.g. `psql`).	Yes
`auto_route_catalog_queries`	`true`	Boolean flag indicating whether to force queries that depend only on system tables to run on the `mz_catalog_server` cluster for improved performance.	Yes
`client_encoding`	`UTF8`	The client’s character set encoding. The only supported value is `UTF-8`.	Yes
`client_min_messages`	`notice`	The message levels that are sent to the client. Accepts values: `debug5`, `debug4`, `debug3`, `debug2`, `debug1`, `log`, `notice`, `warning`, `error`. Each level includes all the levels that follow it.	Yes
`datestyle`	`ISO, MDY`	The display format for date and time values. The only supported value is `ISO, MDY`.	Yes
`emit_introspection_query_notice`	`true`	Whether to print a notice when querying replica introspection relations.	Yes
`emit_timestamp_notice`	`false`	Boolean flag indicating whether to send a `notice` specifying query timestamps.	Yes
`emit_trace_id_notice`	`false`	Boolean flag indicating whether to send a `notice` specifying the trace ID, when available.	Yes
`enable_rbac_checks`	`true`	Boolean flag indicating whether to apply RBAC checks before executing statements.	Yes
`enable_session_rbac_checks`	`false`	Boolean flag indicating whether RBAC is enabled for the current session.	No
`extra_float_digits`	`3`	Boolean flag indicating whether to adjust the number of digits displayed for floating-point values.	Yes
`failpoints`		Allows failpoints to be dynamically activated.	No
`idle_in_transaction_session_timeout`	`120s`	The maximum allowed duration that a session can sit idle in a transaction before being terminated. If this value is specified without units, it is taken as milliseconds (`ms`). A value of zero disables the timeout.	Yes
`integer_datetimes`	`true`	Boolean flag indicating whether the server uses 64-bit-integer dates and times.	No
`intervalstyle`	`postgres`	The display format for interval values. The only supported value is `postgres`.	Yes
`is_superuser`		Reports whether the current session is a superuser with admin privileges.	No
`max_aws_privatelink_connections`	`0`	The maximum number of AWS PrivateLink connections in the region, across all schemas.	Contact support
`max_clusters`	`10`	The maximum number of clusters in the region	Contact support
`max_connections`	`5000`	The maximum number of concurrent connections in the region	Contact support
`max_credit_consumption_rate`	`1024`	The maximum rate of credit consumption in a region. Credits are consumed based on the size of cluster replicas in use.	Contact support
`max_databases`	`1000`	The maximum number of databases in the region.	Contact support
`max_identifier_length`	`255`	The maximum length in bytes of object identifiers.	No
`max_kafka_connections`	`1000`	The maximum number of Kafka connections in the region, across all schemas.	Contact support
`max_mysql_connections`	`1000`	The maximum number of MySQL connections in the region, across all schemas.	Contact support
`max_objects_per_schema`	`1000`	The maximum number of objects in a schema.	Contact support
`max_postgres_connections`	`1000`	The maximum number of PostgreSQL connections in the region, across all schemas.	Contact support
`max_query_result_size`	`1073741824`	The maximum size in bytes for a single query’s result.	Yes
`max_replicas_per_cluster`	`5`	The maximum number of replicas of a single cluster	Contact support
`max_result_size`	`1 GiB`	The maximum size in bytes for a single query’s result.	Contact support
`max_roles`	`1000`	The maximum number of roles in the region.	Contact support
`max_schemas_per_database`	`1000`	The maximum number of schemas in a database.	Contact support
`max_secrets`	`100`	The maximum number of secrets in the region, across all schemas.	Contact support
`max_sinks`	`25`	The maximum number of sinks in the region, across all schemas.	Contact support
`max_sources`	`25`	The maximum number of sources in the region, across all schemas.	Contact support
`max_tables`	`200`	The maximum number of tables in the region, across all schemas	Contact support
`mz_version`	Version-dependent	Shows the Materialize server version.	No
`real_time_recency`	`false`	Boolean flag indicating whether real-time recency is enabled for the current session.	Contact support
`real_time_recency_timeout`	`10s`	Sets the maximum allowed duration of `SELECT` statements that actively use real-time recency. If this value is specified without units, it is taken as milliseconds (`ms`).	Yes
`server_version_num`	Version-dependent	The PostgreSQL compatible server version as an integer.	No
`server_version`	Version-dependent	The PostgreSQL compatible server version.	No
`sql_safe_updates`	`false`	Boolean flag indicating whether to prohibit SQL statements that may be overly destructive.	Yes
`standard_conforming_strings`	`true`	Boolean flag indicating whether ordinary string literals (`'...'`) should treat backslashes literally. The only supported value is `true`.	Yes
`statement_timeout`	`10s`	The maximum allowed duration of the read portion of write operations; i.e., the `SELECT` portion of `INSERT INTO ... (SELECT ...)`; the `WHERE` portion of `UPDATE ... WHERE ...` and `DELETE FROM ... WHERE ...`. If this value is specified without units, it is taken as milliseconds (`ms`).	Yes
`timezone`	`UTC`	The time zone for displaying and interpreting timestamps. The only supported value is `UTC`.	Yes

Aliased configuration parameters

There are a few configuration parameters that act as aliases for other configuration parameters.

schema: schema is an alias for search_path. Only one schema can be specified using this syntax. The TO and = syntax are optional.
names: names is an alias for client_encoding. The TO and = syntax must be omitted.
time zone: time zone is an alias for timezone. The TO and = syntax must be omitted.

Examples

Set active cluster

SHOW cluster;

 cluster
---------
 default

SET cluster = 'quickstart';

SHOW cluster;

  cluster
------------
 quickstart

Set transaction isolation level

SET transaction_isolation = 'serializable';

Set search path

SET search_path = public, qck;

SET schema = qck;

SET