# Schema changes

### Definition

The count of schema alterations (column additions, removals, or data-type changes) detected since the previous scan. Any schema change is treated as an anomaly.

### Source

metadata

### Computation

No sampling used. The value is calculated through the difference of two full table definitions.

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# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://docs.soda.io/data-observability/metric-monitoring-dashboard/dataset-monitors/metadata-based/schema-changes.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.