> ## Documentation Index
> Fetch the complete documentation index at: https://docs.activeviam.com/llms.txt
> Use this file to discover all available pages before exploring further.

# atoti_directquery_bigquery.ConnectionConfig

### *final class* atoti\_directquery\_bigquery.ConnectionConfig

Config to connect to a BigQuery database.

### Example

```pycon theme={"languages":{"custom":["/engine/python-sdk/0.9/languages/pycon.tmLanguage.json"]}}
>>> from atoti_directquery_bigquery import ConnectionConfig
>>> connection_config = ConnectionConfig()
>>> external_database = session.connect_to_external_database(connection_config)
```

#### auto\_multi\_column\_array\_conversion *: [AutoMultiColumnArrayConversion](./atoti.directquery.array_conversion.auto_multi_column_array_conversion#atoti.AutoMultiColumnArrayConversion) | [None](https://docs.python.org/3/library/constants.html#None)* *= None*

When not `None`, multi-column array conversion will be performed automatically.

#### cache *: [bool](https://docs.python.org/3/library/functions.html#bool)* *= True*

Whether to look for query results in the external database query cache.

#### column\_clustered\_queries *: 'all' | 'feeding'* *= 'feeding'*

Control which queries will use clustering columns.

#### credentials *: [Path](https://docs.python.org/3/library/pathlib.html#pathlib.Path) | [None](https://docs.python.org/3/library/constants.html#None)* *= None*

The path to the [BigQuery credentials file](https://cloud.google.com/docs/authentication/getting-started#setting_the_environment_variable).

If `None`, the [application default credentials](https://cloud.google.com/java/docs/reference/google-auth-library/latest/com.google.auth.oauth2.GoogleCredentials#com_google_auth_oauth2_GoogleCredentials_getApplicationDefault__) will be used.

#### feeding\_query\_timeout *: Duration* *= datetime.timedelta(seconds=3600)*

Timeout for queries performed on the external database during feeding phases.

The feeding phases are:

* the initial load to feed [`aggregate_providers`](./atoti.Cube.aggregate_providers#atoti.Cube.aggregate_providers) and [`hierarchies`](./atoti.Cube.hierarchies#atoti.Cube.hierarchies);
* the refresh operations.

#### lookup\_mode *: 'allow' | 'warn' | 'deny'* *= 'warn'*

Whether lookup queries on the external database are allowed.

Lookup can be very slow and expensive as the database may not enforce primary keys.

#### max\_sub\_queries *: Annotated\[[int](https://docs.python.org/3/library/functions.html#int), Field(gt=0)]* *= 500*

Maximum number of sub queries performed when splitting a query into multi-step queries.

#### query\_timeout *: Duration* *= datetime.timedelta(seconds=300)*

Timeout for queries performed on the external database outside feeding phases.

#### time\_travel *: [bool](https://docs.python.org/3/library/functions.html#bool)* *= True*

Whether to use time travel in queries.