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

# Schema & Profiling Tab

> View and manage your source schema, run data profiling, and preview sample data.

The **Schema & Profiling** tab provides a central view for inspecting your source and asset schema, running data profiling, and previewing sample rows.

![The Schema & Profiling tab showing the field list with profiling statistics](https://mintcdn.com/validio/36lh-6_uXUsulPvT/images/docs/schema-and-profiling/760-schema-profiling-tab.png?fit=max\&auto=format\&n=36lh-6_uXUsulPvT\&q=85\&s=42123276883b9c46bb6e8d3d8db12005)

Schema & Profiling tab for a source

## Schema list

The table displays the detected schema for your source and catalog asset, including field names, data types, nullability settings, and profiled statistics.

From this section you can:

* View the full list of fields, their data types, descriptions, and statistics.
* Open the [Schema field sidebar](#schema-field-sidebar) to inspect an individual field's metadata, profiling, glossary terms, and tags.
* **Search** for a specific field; filter by **Data type**, **Glossary** term, **Classification**, and data quality **Dimension**; and **Sort** the list order.
* Update nullability settings and data types to better reflect your data structure. (The **Update schema** button is available for sources, but not for catalog assets.)

For details on how Validio automatically derives schemas through metadata reading, inference, and manual configuration, see [Schema Detection](https://docs.validio.io/v10.2/docs/schema-and-profiling/schema-detection.md).

## Schema field sidebar

The **Schema field sidebar** is a contextual panel that shows the metadata, profiling statistics, glossary terms, and tags of a single schema field. Open it from the **Schema & Profiling** tab or from the **Lineage** graph to inspect or edit a field without leaving your current view.

### Open the sidebar

* In the **Fields** table on the **Schema & Profiling** tab, click a row.
* On the [Lineage](https://docs.validio.io/v10.2/docs/lineage/using-lineage.md) page, expand a schema node and click a field row.

Selecting a field pins a `fieldId` query parameter to the URL so the view is shareable. Close the sidebar to clear the selection from the URL.

### Sidebar contents and actions

Each section of the sidebar shows specific field information and exposes the related actions:

* **Header** — Field path, data-type icon, and an editable multi-origin description with markdown support. Edit the description inline (requires the `catalogAssets:WRITE` permission — see [Managing Roles](https://docs.validio.io/v10.2/docs/access-and-settings/settings/managing-roles.md)), [generate one with AI](https://docs.validio.io/v10.2/docs/ai-features/ai-description-generation.md) using a configured [LLM credential](https://docs.validio.io/v10.2/docs/integrations/llm-credentials.md), or click **View Asset Lineage** to open the asset's lineage with this field preselected.
* **General** — Nullability indicator.
* **Statistics** — Profiling metrics and data-type-specific stats. Displays "No profiling" when none has been collected. For more information, see [Data Profiling](https://docs.validio.io/v10.2/docs/schema-and-profiling/data-profiling.md).
* **Glossary terms** — Assigned terms, with propagation indicators showing when a term was inherited from an upstream field. Assign or unassign terms inline. For more information, see [Glossary Term Assignments](https://docs.validio.io/v10.2/docs/catalog/business-glossary/glossary-term-assignments.md) and [Glossary Term Propagation](https://docs.validio.io/v10.2/docs/catalog/business-glossary/glossary-term-propagation.md).
* **Tags** — Applied tags with creation and update metadata and origin source. Add or manage tags inline. For more information, see [Managing Tags](https://docs.validio.io/v10.2/docs/access-and-settings/settings/managing-tags.md).

## Profile and sample your data

Two actions on this tab read from your data directly:

> **[Profile data](https://docs.validio.io/v10.2/docs/schema-and-profiling/data-profiling.md)**
>
> Run statistical analysis across your fields — null percentages, unique values, and per-type metrics — to inform which validators to configure.

> **[Sample data](https://docs.validio.io/v10.2/docs/schema-and-profiling/data-sampling.md)**
>
> Preview real rows from your source to check that values match the detected schema before setting up filters and segmentation.

Click **Profile data** or **Sample data** on the tab, configure the run in the dialog, and results appear inline for each field.