# Directory

The **Directory** is the catalog's **browse-oriented** entry point. Where [Search](/features/data-discovery/search.md) is query-driven (you know what you're looking for and type a term), the Directory is hierarchy-driven (you don't yet know the exact entity name and want to drill down through known structure). It's the second of the two top-level navigation paths into the catalog.

## When to use the Directory

Reach for the Directory when:

* You want to see **what data sources are registered** in the platform without scrolling through search facets.
* You know the **kind of source** (PostgreSQL, Snowflake, Kafka, Airflow, ...) but not the specific instance or entity.
* You're auditing **per-source coverage** — how many entities did the collector pull from each source, and which entity types are present.
* You're onboarding a teammate and want to walk them through the catalog visually before showing them search.

For everything else — full-text lookup, faceted filtering by tags / domains / owners — use the [Search](/features/data-discovery/search.md) tab.

![Directory level 1 — one card per ODDRN-prefix data source type registered in the platform; each card carries the type's display name and the total entity count across every data source of that type. Clicking a card drills down to level 2.](/files/quOH5Wp8Vc3ueZ9LuGzJ)

## Navigation hierarchy

The Directory is a four-level drill-down. Each level is its own UI page (and its own API endpoint — see below).

| Level                                                           | What you see                                                                                                                                                                                                                                                  | URL                                                                                               |
| --------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------- |
| 1. **Data source types**                                        | One card per ODDRN prefix that the platform's registered data sources resolve to (`postgresql`, `snowflake`, `kafka`, `airflow`, `mysql`, ...). Each card shows the type's display name and a total entity count across every registered source of that type. | `/directory`                                                                                      |
| 2. **Data sources** of the selected type                        | The list of registered data source instances for the chosen type — name, ODDRN-derived properties (host, port, database, ...), and per-source entity count.                                                                                                   | `/directory/{type-prefix}`                                                                        |
| 3. **Entity types** within the selected data source             | The distinct [Data Entity classes](/introduction/main-concepts.md) present in the chosen data source (Dataset, Transformer, Transformer Run, Quality Test, Quality Test Run, Consumer, Input, Group, Relationship, ...).                                      | `/directory/{type-prefix}/{data-source-id}/all` (UI surfaces this on the data-source detail page) |
| 4. **Entities** of the selected (data source, entity type) pair | The paged list of data entities matching both filters; click an entity to land on its detail page (Overview tab).                                                                                                                                             | `/directory/{type-prefix}/{data-source-id}/{type-id}`                                             |

The Directory's **first level** also surfaces in a condensed form on the Catalog Overview home page under the "Directory" section — a quick-jump card grid that links directly into level 2.

## API surface

The Directory's four backing endpoints are documented at [API Reference → Directory](/developer-guides/api-reference/directory.md) — one `GET` endpoint per drill-down level under `/api/directory`, with the level-1 ODDRN-parsing implementation detail included alongside.

## Where it sits in the UI

* **Top-navigation `Catalog`** drops the user on the Search-first landing.
* **Top-navigation `Directory`** opens the standalone level-1 view (`/directory`).
* **Catalog Overview page → Directory section** renders the same level-1 cards inline (so the home page surfaces both Search and Directory entry points side by side).

## Where to next

* [Search and Filtering](/features/data-discovery/search.md) — the query-oriented counterpart, with seven facets.
* [ODDRN](/introduction/main-concepts.md#oddrn) — the addressing scheme whose prefix is what the level-1 cards group by.
* [Main Concepts → Data Discovery](/introduction/main-concepts.md) — where Search and the Directory sit in the broader governance map.


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