# SET Modify the value of a configuration parameter in the current session. `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`](../show). ## Syntax ```mzsql SET [SESSION|LOCAL] TO|= ; ``` Syntax element | Description ------------------------------|------------ **SESSION** | Optional. Set the value for the duration of the current session. **_(Default)_** **LOCAL** | Optional. If specified, set the value for the duration of a single transaction. `` | The name of the configuration parameter to modify. `` | The value to assign to the parameter. **DEFAULT** | Use the parameter's default value. Equivalent to [`RESET`](../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](/overview/isolation-level/).

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` | `1000` | 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 `network_policy` | `default` | The default network policy for the region. | Yes `real_time_recency` | `false` | Boolean flag indicating whether [real-time recency](/get-started/isolation-level/#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](/get-started/isolation-level/#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 [Contact support]: /support ### 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 ```mzsql SHOW cluster; cluster --------- default SET cluster = 'quickstart'; SHOW cluster; cluster ------------ quickstart ``` ### Set transaction isolation level ```mzsql SET transaction_isolation = 'serializable'; ``` ### Set search path ```mzsql SET search_path = public, qck; ``` ```mzsql SET schema = qck; ``` ## Related pages - [`RESET`](../reset) - [`SHOW`](../show)