> ## Documentation Index
> Fetch the complete documentation index at: https://elementary-ele-2784-fix-alerts-configuration-links-docs.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# Schema changes

`elementary.schema_changes`

Executes schema changes monitor that alerts on deleted table, deleted or added columns, or change of data type of a column.
Data Types note: Snowflake, Redshift and Postgres all has "synonym" data types, like `VARCHAR` and `TEXT` in Snowflake. These will be considered as equals by the tests. Types are converted internally to deal with this.

<Info>
  Supported in Databricks with Unity Catalog only. <br />
  Not supported in Athena.
</Info>

<RequestExample>
  ```yml Models
  version: 2

  models:
    - name: < model name >
      tests:
        - elementary.schema_changes
  ```

  ```yml Models example
  version: 2

  models:
    - name: login_events
      tests:
        - elementary.schema_changes:
            tags: ["elementary"]
            config:
              severity: warn
  ```
</RequestExample>