duckdb 1.5.0

DuckDB Python 1.5.0 "Variegata"

on Python PyPI

This is the 1.5.0 release of DuckDB's Python bindings. For a list of changes in DuckDB core, have a look at the DuckDB release notes and the blogpost.

Breaking Changes

• Dropped Python 3.9 support. The minimum supported version is now Python 3.10.
• Removed deprecated duckdb.typing and duckdb.functional modules. These were deprecated in 1.4.0. Use duckdb.sqltypes and duckdb.func instead.
• Renamed column parameter to expression in relational API functions (e.g., min, max, sum, mean, etc.) to better reflect that these accept expressions, not just column names.
• Deprecated fetch_arrow_table() and fetch_record_batch() on connections and relations. Use the new to_arrow_table() and to_arrow_reader() methods instead.

New Features

• Polars LazyFrame projection and filter pushdown. DuckDB can now push down projections and filters when scanning Polars LazyFrames, including support for cast nodes and unstrict casts.
• Polars Int128 / UInt128 support.
• VARIANT type support — Python conversion, NumPy array wrapping, and type stubs.
• TIME_NS type support — nanosecond-precision time values across Python, NumPy, and Spark type systems.
• Profiling API — new get_profiling_info() and get_profiling_json() methods on connections, plus a refactored query_graph module with improved HTML visualization (dark mode, expandable phases, depth).
• to_arrow_table() and to_arrow_reader() — new methods on connections and relations as the preferred Arrow export API.

Performance

• __arrow_c_stream__ on relations — relations now export via the Arrow PyCapsule interface using PhysicalArrowCollector for zero-copy streaming.
• Unified Arrow stream scanning via __arrow_c_stream__, with filter pushdown only when pyarrow is present.
• Arrow schema caching to avoid repeated lookups during scanning.
• Arrow object type caching to avoid repeated detection.
• Empty params treated as None for .sql() — avoids unnecessary parameter binding overhead.
• Simplified GIL management for FetchRow.

Bug Fixes

• Fixed Python object leak in scalar UDFs — PyObject_CallObject return values are now properly stolen to avoid reference count leaks.
• Fixed reference cycle between connections and relations that could prevent garbage collection.
• Relations now hold a reference to their connection, preventing premature connection closure.
• Fixed fsspec race condition in the Python filesystem implementation.
• Fixed numeric conversion logic — improved handling of large integers (fallback to VARCHAR) and UNION types.
• pyarrow.dataset import is now optional — no longer fails if pyarrow is installed without the dataset module.
• Thrown a reasonable error when an Arrow array stream has already been consumed.

Build & Packaging

• jemalloc enabled on Linux x86_64 only (aligned with DuckDB core), removed as a separately bundled extension.
• MSVC runtime linked statically on Windows — eliminates the VS2019 workaround from duckdb/duckdb#17991.