Paths beginning abfss:// point into this: Azure Storage with the hierarchical namespace switched on. In Unity Catalog it is typically the object store under both external locations and managed storage.
Also called Azure Data Lake Storage.
Read more: Microsoft Learn
In the Ultra Transcenders books
Each book explains ADLS in context, with comparison tables and the common traps.
Terms in this definition
- Azure Storage
You reach this Azure data storage platform through a storage account; it covers blobs (Data Lake Storage included), file shares, queues and tables.
- Hierarchical namespace
Enabling this option on a GPv2 storage account makes it ADLS Gen2, bringing directories and ACLs.
- Unity Catalog
Azure Databricks' governance solution covering both data and AI in one place, with centralised permissions, auditing, data discovery and lineage.
- External
API Management virtual network mode in which the gateway stays public but can call private back ends inside the VNet.
- General-purpose v1
The older storage account kind (
Storage), which lacks access tiers, Archive and premium file shares and retires on 13 October 2026. Converting to ZRS requires first upgrading to GPv2, a one-way change.
Related terms
- Access Connector for Azure Databricks
An Azure resource, provided by Microsoft, whose job is to carry a managed identity (system-assigned, user-assigned or both) that Unity Catalog can use. Storage credentials point at the connector's resource ID to gain access to ADLS.
- Credential passthrough
Older Premium-tier Azure Databricks feature that let users reach ADLS under their own identity; it has been deprecated since Databricks Runtime 15.0, and Unity Catalog is the recommended replacement.
- Data Lake Storage Gen1
First generation of Azure Data Lake storage, which reached retirement in February 2024; ADLS Gen2 is its successor.
- File system view
When you point Power Query at a folder-type source (a local folder, a SharePoint folder, Azure Blob storage or Azure Data Lake Storage), it returns a listing in which each file appears once, holding its contents as a binary value plus metadata like its name, file type and path.
- GCS
Object storage offered by Google Cloud. Alongside Amazon S3, ADLS and Blob Storage, it is a source Auto Loader can ingest from.
- Storage credential
Wraps a long-lived credential, often an Access Connector's managed identity, that external locations use to reach ADLS. It is a Unity Catalog securable, and
CREATE STORAGE CREDENTIALis needed to make one.