The older metastore for tables that aren't in Unity Catalog. Through Hive metastore federation, Unity Catalog can govern its tables, which also serves serverless compute since that has no direct support for it.
Also called Hive metastore.
Read more: Databricks docs
In the Ultra Transcenders books
Each book explains HMS in context, with comparison tables and the common traps.
Terms in this definition
- Metastore
The highest-level Unity Catalog container, holding metadata and permissions for a single cloud region. Each region has only one, which every workspace in that region shares, and it is not meant to be the usual boundary for isolating data.
- Unity Catalog
Azure Databricks' governance solution covering both data and AI in one place, with centralised permissions, auditing, data discovery and lineage.
- Federation
An arrangement in which separate identity providers trust one another, letting people use the account from their home organisation to reach services in another domain. In a hybrid setup, Entra ID can pass sign-ins over to a federation service like AD FS.
- Govern
The part of the Cloud Adoption Framework concerned with keeping cloud use under control by setting guardrails made of policies, procedures and tools. It runs continuously across the estate alongside Secure and Manage.
- Serverless compute
Azure Machine Learning compute provided on demand whenever a job names no compute target. No cluster needs creating or managing, and jobs do not wait in a queue behind one another.
Related terms
- ABAC DENY policy
A Beta policy type that blocks
MANAGE ACCESS CONTROLwherever a securable carries matching governed tags; even ownership or an explicit grant can't get round it. The legacy Hive metastore's SQLDENYis a different thing. - Authorised paths
Cloud storage locations specified when creating a foreign catalog for Hive metastore federation. Tables reached through the catalog have to live beneath these locations, so changing a table's location can't be used to get at other data.