Manage schemas
This article shows how to view, update, and delete schemas in Unity Catalog.
See also What are schemas in Databricks? and Create schemas.
Note
In Hive metastore, you must use a SQL commands to manage schemas. Behavior in legacy Hive metastore differs from Unity Catalog. Permissions required depend on whether or not you are using table access control. See Schemas in Hive metastore and Hive metastore privileges and securable objects (legacy).
Before you begin
To work with schemas in Unity Catalog:
You must have a Unity Catalog metastore linked to the workspace where you perform the schema creation.
The cluster that you use to run a notebook to manage a schema must use a Unity Catalog-compliant access mode. See Access modes. SQL warehouses always support Unity Catalog.
Permissions required to alter, view, and drop schemas in Unity Catalog are listed in the sections that follow.
Find and view schemas
In Unity Catalog, users can see all schemas on which they have been assigned the USE SCHEMA
permission, along with the USE CATALOG
permission on the schema’s parent catalog. To access or list a table or view in a schema, users must also have SELECT
permission on the table or view.
Log in to a workspace that is linked to the Unity Catalog metastore.
Click Catalog.
In the Catalog pane on the left, click the catalog that contains the schema (
hive_metastore
if it’s in the Hive metastore).
Alternatively, you can search for the schema using the Type to filter field in the Catalog pane.
Run SHOW SCHEMAS
in a notebook or the SQL query editor to list all schemas in a catalog or those that match a regular expression. Run DESCRIBE SCHEMA
to get details about a schema. See SHOW SCHEMAS and DESCRIBE SCHEMA.
Update a schema
To update (or alter) a schema in a Unity Catalog catalog, you can use Catalog Explorer or a SQL command.
Permissions required: Permissions required to update a schema in Unity Catalog depend on the update:
To change the owner, you must be the owner.
To rename the schema, you must be the owner.
To add or update a comment or tags, you must be the owner or have
USE SCHEMA
andMODIFY
on the schema andUSE CATALOG
on the parent catalog.To add a table, you must be the schema owner or have
USE SCHEMA
andCREATE TABLE
on the schema andUSE CATALOG
on the parent catalog.To add a volume, you must be the schema owner or have
USE SCHEMA
andCREATE VOLUME
on the schema andUSE CATALOG
on the parent catalog.To grant and revoke permissions on the schema, you must be the schema owner, the owner of the parent catalog, or a metastore admin.
Log into a workspace that is linked to the Unity Catalog metastore.
Click Catalog.
In the Catalog pane on the left, click the catalog that contains the schema and then click the schema to open the schema details page.
Alternatively, you can search for the schema using the Type to filter field in the Catalog pane.
Use the following page elements on the schema details page to update the schema:
Overview tab: update the owner, add or update tags, add or update comments. See Manage Unity Catalog object ownership, Apply tags to Unity Catalog securable objects, and Add comments to data and AI assets.
Permissions tab: grant and revoke privileges on the schema. See Manage privileges in Unity Catalog.
The kebab menu: Rename the schema.
Create button: create a table or volume in the schema. See Create or modify a table using file upload and What are Unity Catalog volumes?.
To change the owner, add or update tags, set schema properties, and manage predictive optimization on the tables in a schema, run the
ALTER SCHEMA
command in a notebook or the SQL query editor. See ALTER SCHEMA.To grant or revoke privileges, use the
GRANT
orREVOKE
command. See GRANT and REVOKE.To add tables, volumes, and other data and AI assets to a schema, see the documentation for creating the asset (for example What are tables and views? or Manage model lifecycle in Unity Catalog).
To rename a schema using SQL, you must create a new schema and move all assets into the new schema.
Delete a schema
To delete (or drop) a schema in a Unity Catalog catalog, you can use Catalog Explorer or a SQL command.
Permissions required: To drop a schema in Unity Catalog, you must be its owner.
You must delete all tables in the schema before you can delete it.
Log in to a workspace that is linked to the metastore.
Click Catalog.
In the Catalog pane, on the left, click the schema that you want to delete.
In the detail pane, click the kebab menu in the upper right corner and select Delete.
On the Delete schema dialog, click Delete.
Run the following SQL command in a notebook or the SQL query editor. Items in brackets are optional. Replace the placeholder <schema-name>
.
For parameter descriptions, see DROP SCHEMA.
If you use DROP SCHEMA
without the CASCADE
option, you must delete all tables in the schema before you can delete it.
DROP SCHEMA [ IF EXISTS ] <schema-name> [ RESTRICT | CASCADE ]
For example, to delete a schema named inventory_schema
and its tables:
DROP SCHEMA inventory_schema CASCADE
Next steps
To learn how to add tables and volumes to your schema, see What are tables and views? and What are Unity Catalog volumes?.