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

# Drivers

> Declare which metrics feed into another and see those relationships in Saved Trees

**Drivers** are metrics that directly influence or feed into another metric. By defining drivers in your `.yml` files, you can automatically visualize how metrics relate to each other in [Saved Trees](/explore/metrics-catalog/build-saved-trees) — no manual drawing needed.

For example, `total_order_amount` is a driver of `total_revenue`, `average_order_size`, and `total_completed_order_amount` — because each of those metrics is influenced by the total order amount. On the canvas, this creates a tree where `total_order_amount` fans out to the metrics it drives.

### Defining drivers

Add a `drivers` property to any metric listing the metrics that flow into it. You can reference metrics from the same table by name, or from other tables using the `table.metric` syntax:

<CodeGroup>
  ```yaml dbt v1.10+ theme={null}
  models:
    - name: orders
      columns:
        - name: order_amount
          config:
            meta:
              metrics:
                total_revenue:
                  type: sum
                  drivers:
                    - total_order_amount
                average_order_size:
                  type: average
                  drivers:
                    - total_order_amount
                total_completed_order_amount:
                  type: sum
                  drivers:
                    - total_order_amount
  ```

  ```yaml dbt v1.9 and earlier theme={null}
  models:
    - name: orders
      columns:
        - name: order_amount
          meta:
            metrics:
              total_revenue:
                type: sum
                drivers:
                  - total_order_amount
              average_order_size:
                type: average
                drivers:
                  - total_order_amount
              total_completed_order_amount:
                type: sum
                drivers:
                  - total_order_amount
  ```

  ```yaml Lightdash YAML theme={null}
  type: model
  name: orders

  dimensions:
    - name: order_amount

  metrics:
    total_revenue:
      type: sum
      sql: ${TABLE}.order_amount
      drivers:
        - total_order_amount
    average_order_size:
      type: average
      sql: ${TABLE}.order_amount
      drivers:
        - total_order_amount
    total_completed_order_amount:
      type: sum
      sql: ${TABLE}.order_amount
      drivers:
        - total_order_amount
  ```
</CodeGroup>

This creates edges on the canvas pointing from each driver to the current metric (e.g., `total_order_amount` → `total_revenue`, `total_order_amount` → `average_order_size`, etc.).

#### Cross-table drivers

Drivers don't have to live in the same table as the metric they drive. Use the `table.metric` syntax to reference a metric from another table:

```yaml theme={null}
metrics:
  conversion_rate:
    type: number
    sql: ${signups} / ${visits}
    drivers:
      - signups              # same-table metric
      - marketing.ad_spend   # cross-table: 'table.metric_name'
```

### How drivers appear on the canvas

* **Automatic**: Driver edges appear as soon as both the driver and target metrics are on the canvas.
* **Read-only**: You cannot delete or modify driver edges from the UI — they are managed through your `.yml` configuration.

In Saved Trees, driver edges are displayed alongside manually-created edges, giving you a complete picture of both the relationships you've drawn and the ones defined in your data model.

<Info>
  Driver edges cannot be removed from a Saved Tree. If you don't want a driver edge to appear, remove one of its endpoint nodes from the canvas.
</Info>