Connections

Reading from Databricks

Reading from Databricks

When Databricks is the source, the Data read option chooses how rows leave Databricks.

SQL Select

The default. Omni Loader reads each table through the ODBC driver, then writes it to the target like any other source. Works with every target.

Parquet export

Databricks writes each table as Parquet files directly to cloud storage (INSERT OVERWRITE DIRECTORY), and the target loads those files itself. Rows never pass through Omni Loader, which makes this the fastest path for large tables.

Export storageTargets that can load it
Azure Data LakeDatabricks, Fabric Lakehouse, Fabric Warehouse, Azure Synapse
Amazon S3Databricks
The project wizard only offers targets that can load the chosen export. If a project's target can't load it, the run stops before anything is exported.

Databricks export storage

  • Storage: Azure Data Lake or Amazon S3. For Azure, enter the storage account, container and a SAS token. For S3, enter the bucket URL, access key ID and secret access key.
  • Data format: Parquet.
  • Compression: Snappy, Gzip or None.
  • Data handling: what happens to the export folder between runs. Options are Timestamped, Clear before run, Folder per table and Clear after run.
Databricks can write only to a path covered by a Unity Catalog external location on which the connecting principal has WRITE FILES. A Databricks workspace writes only to its own cloud's storage: an Azure workspace exports to Azure Data Lake, an AWS workspace to S3. See Unity Catalog setup.

Loading the export

The target uses the source's storage settings. Its connection shows Use export authentication: leave it on to load with the source's SAS token, or turn it off and enter a SAS token of the target's own. An S3 export brings its keys along, and the Databricks target turns them into temporary credentials for the load.

A Fabric Lakehouse target loads the export with a Spark notebook and needs Service principal authentication. A source filter (WHERE clause) applies to the export too.

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