Notebook compute resources
This article covers the options for notebook compute resources. You can run a notebook on a Databricks cluster, serverless compute, or, for SQL commands, you can use a SQL warehouse, a type of compute-optimized for SQL analytics.
Attach a notebook to a cluster
To attach a notebook to a cluster, you need the CAN ATTACH TO cluster-level permission.
Important
As long as a notebook is attached to a cluster, any user with the CAN RUN permission on the notebook has implicit permission to access the cluster.
To attach a notebook to a cluster, click the compute selector in the notebook toolbar and select a cluster from the dropdown menu.
The menu shows a selection of clusters you have used recently or are currently running.
To select from all available clusters, click More…. Click the cluster name to display a dropdown menu, and select an existing cluster.
You can also create a new cluster by selecting Create new resource… from the dropdown menu.
Important
An attached notebook has the following Apache Spark variables defined.
| Class | Variable Name |
|---|---|
SparkContext |
sc |
SQLContext/HiveContext |
sqlContext |
SparkSession (Spark 2.x) |
spark |
Do not create a SparkSession, SparkContext, or SQLContext. Doing so will lead to inconsistent behavior.
Use a notebook with a SQL warehouse
When a notebook is attached to a SQL warehouse, you can run SQL and Markdown cells. Running a cell in any other language (such as Python or R) throws an error. SQL cells executed on a SQL warehouse appear in the SQL warehouse's query history. The user who ran a query can view the query profile from the notebook by clicking the elapsed time at the bottom of the output.
Running a notebook requires a pro SQL warehouse. You must have access to the workspace and the SQL warehouse.
To attach a notebook to a SQL warehouse do the following:
Click the compute selector in the notebook toolbar. The dropdown menu shows compute resources that are currently running or that you have used recently. SQL warehouses are marked with
.From the menu, select a SQL warehouse.
To see all available SQL warehouses, select More… from the dropdown menu. A dialog appears showing compute resources available for the notebook. Select SQL Warehouse, choose the warehouse you want to use, and click Attach.
You can also select a SQL warehouse as the compute resource for a SQL notebook when you create a workflow or scheduled job.
SQL warehouse limitations
See Known limitations Databricks notebooks for more information.
Detach a notebook
To detach a notebook from a compute resource, click the compute selector in the notebook toolbar and hover over the attached cluster or SQL warehouse in the list to display a side menu. From the side menu, select Detach.
You can also detach notebooks from a cluster using the Notebooks tab on the cluster details page.
Tip
Azure Databricks recommends that you detach unused notebooks from clusters. This frees up memory space on the driver.