Attach a directory of Delta tables as a single DuckDB database with automatic schema discovery
Installing and Loading
INSTALL delta_classic FROM community;
LOAD delta_classic;
Example
-- Load required extensions
LOAD delta;
LOAD delta_classic;
-- Attach a directory of Delta tables as a single database
ATTACH '/path/to/delta/tables' AS mydb (TYPE delta_classic);
-- Query tables directly
SELECT * FROM mydb.main.orders LIMIT 10;
About delta_classic
Delta Classic lets you attach a directory of Delta Lake tables as a single DuckDB database, instead of attaching each table individually. It discovers tables by scanning for subdirectories containing a _delta_log folder.
The extension supports two directory layouts:
- Single-schema: the attached path directly contains Delta tables
- Multi-schema: the attached path contains subdirectories, each treated as a schema, with Delta tables inside them
All Delta reading is delegated to the existing Delta extension via internal ATTACH … (TYPE DELTA). Supports PIN_SNAPSHOT and all storage backends (local filesystem, S3, ABFSS, GCS).
Added Functions
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Overloaded Functions
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