HarborSQL
HarborSQL is an external SQL query engine for Unity Catalog Delta tables.
It accepts Databricks SQL connector-style requests, forwards the caller's
Databricks bearer token to Unity Catalog, vends short-lived table credentials,
opens Delta data with delta-rs, executes read-only SQL with DataFusion, and
returns Databricks-compatible result sets.
Capabilities
- Read-only
SELECTqueries - Unity Catalog Delta table discovery and authorization
- AWS S3-backed temporary table credentials vended by Unity Catalog
- Databricks SQL connector compatibility for a focused Thrift-over-HTTP surface
- DataFusion query execution with Delta Lake table providers
- Bounded in-memory result materialization
- Structured tracing, request IDs, and Prometheus metrics
- Stable client-facing error codes with centrally redacted internal logs
:::caution Pre-1.0 HarborSQL is pre-1.0 software. The compatibility surface is intentionally defined and still growing. Cloud Fetch, durable or streaming result storage, and broader Databricks SQL protocol coverage are not yet part of the default runtime. :::
Start Here
- Getting Started covers the main migration path.
- Advanced Usage covers one-off query mode.
- How It Works explains the request path through Unity Catalog and Delta.
- Configuration lists environment variables and defaults.
- Result Types documents the current Arrow to Thrift mapping.