Catalog
The Catalog gives users a view of the data assets available in their workspace — tables, schemas, ownership, lineage, and access permissions — all in one place.
The supported catalog and current limitations are documented in the
canonical Data Catalog assessment. In the assessed workspace,
only the Superset-registered delta catalog is supported in this UI.
Services Behind This Feature
| Service | Role |
|---|---|
| BFF API | Routes requests from the Cogrion UI to Superset, DataHub, Ranger, and Trino-backed services. |
| Datahub | Stores descriptions, tags, structured properties, and lineage; it does not determine the top-level catalog list. |
| Superset | Data exploration and visualization |
| Trino | Query engine |
| Ranger | Provides the access control layer — permissions visible in the catalog are enforced here at query time. |
| Hive Metastore | Stores schemas and tables for the current Delta and Hive connectors. |
What a Table Detail Page Shows
When a user opens a specific table in the Catalog, they see:
| Tab | Content |
|---|---|
| Overview | Column names, data types, DataHub tags, and descriptions |
| Sample data | A preview of actual row data from the table (fetched via Trino) |
| Permissions | Direct and inherited Ranger permissions |
| History | Delta table history |
| Lineage | Upstream and downstream DataHub relationships, when matching lineage metadata exists |
| Quality | Results from data quality checks run against the table |
Lineage
The Catalog reads lineage from DataHub. It appears only when a producer emits
lineage using the same canonical dataset identity that the Catalog requests.
Current deployment source does not establish complete producer coverage, and
the reviewed UI constructs a different lineage URN from its metadata URN. See
DATA-CAT-001.
Go Deeper
- Sharing & Permissions — grant and revoke table-level access from the Catalog
- Column Tagging — apply tags to columns and how they flow through to Ranger
- Data Access and Authorization — overview of the auth model
- Datahub — the metadata catalog component powering the Catalog UI
- Hive Metastore — the schema catalog that HMS and Trino share