> ## Documentation Index
> Fetch the complete documentation index at: https://forest-chore-open-api.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# ActiveRecord datasource

> Connect Forest to your ActiveRecord models with support for relationships and Live Query

The ActiveRecord datasource enables importing collections from all model classes extending `ActiveRecord::Base`. It automatically respects your ActiveRecord relationships and configurations.

<Warning>
  ActiveRecord datasource is only available for Ruby. For Node.js, check the [Sequelize datasource](/get-started/connect/data-sources/sequelize) or [SQL datasource](/get-started/connect/data-sources/sql).
</Warning>

## Basic usage

```ruby theme={null}
require 'forest_admin_datasource_active_record'

def self.setup!
  ForestAdminDatasourceActiveRecord::Datasource.new(
    {
      'adapter' => ENV['DB_ADAPTER'],
      'host' => ENV['DB_HOST'],
      'username' => ENV['DB_USERNAME'],
      'password' => ENV['DB_PASSWORD'],
      'database' => ENV['DB_DATABASE'],
    }
  )
end
```

## Features

The ActiveRecord datasource automatically preserves your ORM configuration:

* **ActiveRecord relationships** - Relationships will be respected
* **Live Query support** - Users with proper permissions can create Live Query components for charts, analytics, and segments using SQL

## Live Query support

Enable SQL-based reporting by setting a connection name identifier when creating the datasource:

```ruby theme={null}
ForestAdminDatasourceActiveRecord::Datasource.new(
  database_config,
  live_query_connections: 'main_database'
)
```

This allows authorized users to create Live Query charts, analytics, and segments that execute custom SQL directly against your database.

<Warning>
  Live Queries execute raw SQL. Ensure proper access controls and review queries before deploying to production.
</Warning>

## Multi-database configuration

For applications using multiple databases, provide a hash mapping display names to Rails connection identifiers:

```ruby theme={null}
ForestAdminDatasourceActiveRecord::Datasource.new(
  database_config,
  live_query_connections: {
    'main_database' => 'primary',
    'replica_database' => 'primary_replica'
  }
)
```

The configuration keys display in Forest's UI, while the values reference connection names from your `config/database.yml` file.

## Polymorphic relationships

Forest supports polymorphic relationships in ActiveRecord by enabling a specific configuration option on the datasource instance.

### Configuration

To activate polymorphic relationship support, set the second parameter to `true` when instantiating the datasource:

```ruby theme={null}
def self.setup!
  database_configuration = Rails.configuration.database_configuration

  # Enable polymorphic relations with true parameter
  datasource = ForestAdminDatasourceActiveRecord::Datasource.new(
    database_configuration[Rails.env],
    true
  )

  @create_agent = ForestAdminAgent::Builder::AgentFactory.instance.add_datasource(datasource)
  customize
  @create_agent.build
end
```

### Tips

The `id` and `type` fields of polymorphic relationships remain visible in the interface. Hide them through back-end customization or frontend configuration if desired.

### Limitations

#### Collections

* **Removal**: Cannot delete collections that serve as polymorphic relationship targets; attempting this raises: "Cannot remove {CollectionName} because it's a potential target of polymorphic relation"
* **Renaming**: Cannot rename collections involved in polymorphic relationships; error states: "Cannot rename collection {CurrentName} because it's a target of a polymorphic relation"

#### Fields

* **Removal**: Cannot delete fields (`foreign_key_type`, `foreign_key_id`) used in polymorphic relationships
* **Renaming**: Cannot rename fields involved in these relationships
* **Computed Fields**: Cannot use polymorphic relationships as dependencies for computed fields due to unpredictable target collections

#### Search

Extended search functionality skips polymorphic relationships to prevent excessive resource consumption, generating debug logs about this behavior. Implement custom search behavior via documentation.

## Source code

This connector is open source. Browse the code or contribute on GitHub: [`forest_admin_datasource_active_record`](https://github.com/ForestAdmin/agent-ruby/tree/main/packages/forest_admin_datasource_active_record).