Altertable Catalogs

Altertable catalogs are hosted lakehouse databases you create and manage on the Altertable platform. They are the default place to store new data when you want Altertable to handle the catalog, storage layout, and query path for you.

Unlike external catalogs, which connect existing databases, warehouses, or buckets, Altertable catalogs are managed by Altertable from the start. They use Altertable Workers for compute and Buckets for durable object storage.

Each table in an Altertable catalog is backed by Parquet files written to an underlying bucket. Because Altertable controls the full path from SQL execution to file layout, Altertable catalogs are the most optimized catalog type available on the platform.

When to use Altertable catalogs

Use an Altertable catalog when you want to:

• Create new lakehouse tables without provisioning your own database.
• Store durable data in open Parquet files.
• Let Altertable optimize file layout, caching, and query execution together.
• Query managed tables alongside external catalogs in the same SQL engine.

Learn more

• Workers: Workers that execute SQL and cache hot data
• Buckets: Buckets that store catalog files
• External Catalogs: Connect existing databases, warehouses, and buckets