Apply tags to Unity Catalog securable objects

This page shows how to apply tags to Unity Catalog securable objects.

Tags are attributes that include keys and optional values that you can use to organize and categorize securable objects in Unity Catalog. Using tags also simplifies the search and discovery of tables and views using the workspace search functionality.

warning

Tag data is stored as plain text and may be replicated globally. Do not use tag names, values, or descriptors that could compromise the security of your resources. For example, do not use tag names, values or descriptors that contain personal or sensitive information.

Supported securable objects

Securable object tagging is currently supported on catalogs, schemas, tables, table columns, volumes, views, registered models, and model versions. For more information about securable objects, see Securable objects in Unity Catalog.

Governed tags

Preview

This feature is in Public Preview.

Governed tags are account-level tags with enforced rules for consistency and control. Using governed tags, you define the allowed keys and values and control which users and groups can assign them to objects. This ensures tags are applied consistently and conform to organizational standards, giving centralized control over classification, compliance, and operations.

Governed tags:

• Can only be assigned or modified by users or groups with the appropriate permissions.

• Must use values defined in the associated tag policy.

• Are marked in UI with a lock .

  

If a governed tag is deleted, the associated tags become ungoverned. The tags remain on objects, but anyone can assign or modify them without requiring permissions. Users with the right privileges can continue creating and assigning tags that are not governed.

For more information, see Governed tags.

note

If you are enrolled in the dashboard tags Private Preview, any tag assigned to a dashboard that matches the name of a governed tag is automatically subject to that tag’s policy.

System tags

System tags are a special type of governed tag that are predefined by Databricks. System tags have a few distinct characteristics:

• System tag definitions (keys and values) are predefined by Databricks.

• Users cannot modify or delete system tag keys or values.

• Users can control who is allowed to assign or unassign system tags through governed tag permission settings.

• A wrench is displayed next to the tag.

  

System tags are designed to support standardized tagging across organizations, particularly for use cases like data classification, ownership, or lifecycle tracking. By using predefined, governed tag definitions, system tags help enforce consistency without requiring users to manually define or manage tag structures.

Requirements

To add tags to Unity Catalog securable objects, you must own the object or have all of the following privileges:

• APPLY TAG on the object
• USE SCHEMA on the object's parent schema
• USE CATALOG on the object's parent catalog

To add a governed tag to Unity Catalog securable objects, you must also have the ASSIGN permission on the governed tag. See Manage permissions on governed tags.

Constraints

The following is a list of tag constraints:

• Tag keys are case sensitive. For example, Sales and sales are two distinct tags.

• You can assign a maximum of 50 tags to a single securable object.

• The maximum length of a tag key is 255 characters.

• The maximum length of a tag value is 1000 characters.

• The following characters are not allowed in tag keys:

  . , - = / :

• Trailing and leading spaces are not allowed in tag keys or values.

• Tag search using the workspace search UI is supported only for tables and views.

• Tag search requires exact term matching.

Add and update tags using Catalog Explorer

To add and update securable object tags using Catalog Explorer:

1. Click Catalog in the sidebar.

2. Select a securable object.

3. On the object Overview page, add or update a tag:

   • Tags that are governed are in the Governed section header and have a lock icon.
   • If there are no tags, click the Add tags button.
   • If there are tags, click the Add/Edit tags icon.

   You can use the Add/Edit tags dialog to add and delete multiple tags.

   Tag keys are required. Tag values are optional.

   To add or delete table column tags, click the Add tag icon.

Add and update tags using SQL commands

note

This feature is available in Databricks Runtime versions 13.3 and above.

You can use the ALTER <object> SQL command to tag catalogs, schemas, tables (including views, materialized views, streaming tables), volumes, and table columns. For example, you can use the SET TAGS and UNSET TAGS clauses with ALTER TABLE to manage tags on a table. See DDL statements for a list of available Data Definition Language (DDL) commands and their syntax.

For registered models, you must use Catalog Explorer or the MLflow ClientAPI. See Use tags on models.

Use tags to search for tables

Use the Databricks workspace search bar to search for tables and views using tag keys and tag values. You can use both table tags to search. You cannot use tags to search for other tagged objects, like table columns, catalogs, schemas, or volumes.

Only tables and views that you have permission to see appear in search results. This means that you must have at least the BROWSE privilege on the object (or on the object's parent catalog and schema) to return the object in search results.

For details, see Use tags to search for tables.

Retrieve tag information from information schema tables

Each catalog created in Unity Catalog includes an INFORMATION_SCHEMA. This schema includes tables that describe the objects known to the schema's catalog. You must have the appropriate privileges to view the schema information.

You can query the following to retrieve tag information:

• INFORMATION_SCHEMA.CATALOG_TAGS
• INFORMATION_SCHEMA.COLUMN_TAGS
• INFORMATION_SCHEMA.SCHEMA_TAGS
• INFORMATION_SCHEMA.TABLE_TAGS
• INFORMATION_SCHEMA.VOLUME_TAGS

For more information, see Information schema.