# Where to Log

By default, all data is logged to the current working directory to `default.sqlite` (`sqlite:///default.sqlite`).

## Supported Databases

TruLens supports logging to any SQLAlchemy-compatible database:

- **SQLite** (default) - No additional setup required
- **[PostgreSQL](/content/component_guides/logging/where_to_log/log_in_postgres/index.html)** - Open-source relational database
- **[Snowflake](/content/component_guides/logging/where_to_log/log_in_snowflake/index.html)** - Cloud data warehouse
- **MySQL** - Open-source relational database

## Connecting with a Database URL

Data can be logged to a SQLAlchemy-compatible database referred to by `database_url` in the format `dialect+driver://username:password@host:port/database`.

See [this article](https://docs.sqlalchemy.org/en/20/core/engines.html#database-urls) for more details on SQLAlchemy database URLs.

Connecting with a Database URL

```
from trulens.core import TruSession

session = TruSession(
    database_url="postgresql://username:password@localhost:5432/mydatabase"
)
```

## Connecting with a Database Engine

Data can also be logged to a SQLAlchemy-compatible engine referred to by `database_engine`. This is useful when you need to pass keyword args in addition to the database URL to connect to your database, such as [`connect_args`](https://docs.sqlalchemy.org/en/20/core/engines.html#sqlalchemy.create_engine.params.connect_args).

Connecting with a Database Engine

```
from trulens.core import TruSession
from sqlalchemy import create_engine

engine = create_engine(
    "postgresql://username:password@localhost:5432/mydatabase",
    connect_args={"sslmode": "require"},
)

session = TruSession(database_engine=engine)
```