Monitor usage with system tables

Preview

This article explains the concept of system tables in Databricks and highlights resources you can use to get the most out of your system tables data.

What are system tables?

System tables are a Databricks-hosted analytical store of your account’s operational data. System tables can be used for historical observability across your account.

Which system tables are available?

Currently, Databricks hosts system tables for:

Audit logs: Located at system.access.audit.
Billable usage logs: Located at system.billing.usage.
Pricing table: Located at system.billing.list_prices.
Table and column lineage: Both tables located under system.access.
Marketplace listing access: Located at system.marketplace.listing_access_events.

Note

You may see other system tables in your account besides the ones listed above. Those tables are in Private Preview currently and are empty by default. If you are interested in using any of these tables, please reach out to your Databricks account team.

Enable system tables

Since system tables are governed by Unity Catalog, you need to have at least one Unity Catalog-enabled workspace in your account to enable and access system tables. System tables include data from all workspaces in your account but they can only be accessed from a Unity Catalog-enabled workspace.

System tables must be enabled by an account admin. You can enable system tables using the Unity Catalog REST API.

List available system schemas

Use the following curl command to list available system schemas:

curl -v -X GET -H "Authorization: Bearer <PAT Token>" "https://<workspace>.cloud.databricks.com/api/2.0/unity-catalog/metastores/<metastore-id>/systemschemas"

The following is an example output of the GET command:

{"schemas":[{"schema":"access","state":"<AVAILABLE OR EnableCompleted>"},{"schema":"billing","state":"<AVAILABLE OR EnableCompleted>"},{"schema":"information_schema","state":"<AVAILABLE OR EnableCompleted>"}]}

state: AVAILABLE: The system schema is available but has not yet been enabled.

state: EnableCompleted: You have enabled the system schema and it is visible in Catalog Explorer.

Enable a system schema

Use the following curl command to enable a system schema:

curl -v -X PUT -H "Authorization: Bearer <PAT Token>" "https://<workspace.databricks.com/api/2.0/unity-catalog/metastores/<metastore-id>/systemschemas/<SCHEMA_NAME>"

If the system schema is enabled successfully, result code 200 is returned.

If you attempt to re-enable a system schema, the following is returned: "error_code":"SCHEMA_ALREADY_EXISTS","message":"Schema <schema-name> already exists".

Disable a system schema

Use the following curl command to disable a system schema:

curl -v -X DELETE -H "Authorization: Bearer <PAT Token>" "https://<workspace>.databricks.com/api/2.0/unity-catalog/metastores/<metastore-id>/systemschemas/<SCHEMA_NAME>"

Grant access to system tables

System tables access is governed by Unity Catalog. By default, no users have access to system tables. To grant access, metastore admins must grant USE and SELECT permissions on the select system schemas. See Manage privileges in Unity Catalog.

Note

System tables are read-only and cannot be modified.

Do system tables contain data for all workspaces in your account?

The audit log and lineage tables contain operational data for all workspaces in your account deployed within the same cloud region. The billing system table (system.billing.usage) contains data for all workspaces in your account, no matter what region they are deployed in.

Even though system tables can only be accessed through a Unity Catalog workspace, the tables also include operational data for non-Unity Catalog workspaces in your account.

Where are the system tables located?

The system tables in your account are located in a catalog called system, which is included in every Unity Catalog metastore. In the system catalog you’ll see schemas such as access and billing that contain the system tables.

Note

During the system tables Public Preview, Databricks will retain all your system tables data.

Limitations

The system tables public preview currently has the following limitations:

No support for real-time monitoring. Data is updated throughout the day. If you don’t see a log for a recent event, check back later.

Known issues

The system schemas system.operational_data and system.lineage might contain empty tables.
The system schemas system.access and system.billing are in Public Preview and available to all customers. Databricks recommends using Public Preview system schemas only.

If your workspace uses a customer-managed VPC, you might be denied access to the S3 bucket where the logs are stored. If so, you need to update your VPC endpoint policy to allow access to the S3 bucket where your region’s system tables data is stored. For a list of regional bucket names, see the System tables bucket column in Storage bucket addresses table.