Install and load the extension: INSTALL delta; LOAD delta
Read a local Delta table: SELECT * FROM delta_scan('/path/to/delta_table')
Read a Delta table on S3: first configure S3 credentials (via CREATE SECRET or the aws extension), then SELECT * FROM delta_scan('s3://bucket/path/to/delta_table')
Use predicates normally; delta_scan pushes partition filters and column projections to skip unnecessary files
Inspect the table schema: DESCRIBE SELECT * FROM delta_scan('path/to/delta_table')
Known gotchas
delta_scan points to the table root directory, which must contain the '_delta_log' folder; pointing to a subdirectory or a Parquet file directly will cause an error
The delta extension is built on the Delta Kernel library; it does not yet support all Delta Lake features such as Deletion Vectors uniformly across versions — check the extension release notes for feature coverage
For cloud storage paths, S3 credentials must be configured before calling delta_scan; unlike some other DuckDB functions, delta_scan does not fall back to environment-variable credential discovery automatically in all versions
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