---
updatedAt: 2026-06-03T08:47:40.000Z
agentTools:
  projectIndex: https://docs.getmontecarlo.com/llms.txt
---

# Comparison (deprecated)

Blocked — creation disabled. Use metric_comparison instead.

> **Blocked — creation permanently disabled.** The `comparison` YAML key is recognized by the CLI but creation is blocked with: `"Creating legacy comparison monitors is no longer supported. Use the v2 metric_comparison monitor instead."`

## What to use instead

Use [`metric_comparison`](https://docs.getmontecarlo.com/docs/metric-comparison) for all comparison monitors. It provides a cleaner source/target structure with explicit SQL and warehouse configuration.

```yaml
montecarlo:
  metric_comparison:
    - name: orders_source_target
      description: Compare order counts between warehouses
      source:
        sql: SELECT COUNT(*) FROM analytics.orders
        warehouse: warehouse_a
      target:
        sql: SELECT COUNT(*) FROM analytics.orders
        warehouse: warehouse_b
      alert_conditions:
        - type: comparison_delta
          metric: ROW_COUNT
          operator: GT
          threshold_value: 10
      schedule:
        type: fixed
        interval_minutes: 720
      domains:
        - my-domain
```

## Migration steps

1. Identify existing `comparison` monitors in your YAML files.
2. Rewrite each as `metric_comparison` using the source/target structure above.
3. Apply with `montecarlo monitors apply`.