Error5 reports
Fix ArrowNotImplementedError
in Datasets
✅ Solution
ArrowNotImplementedError in datasets often arises when the underlying Arrow library lacks support for casting between specific data types, especially for complex nested structures or multimedia data. To fix this, either upgrade to the latest version of `pyarrow` and `datasets` which may contain the necessary casting implementations, or restructure your dataset/features to use simpler Arrow-compatible datatypes, potentially involving manual serialization/deserialization where direct casting isn't available.
Related Issues
Real GitHub issues where developers encountered this error:
Cannot load dataset, fails with nested data conversions not implemented for chunked array outputsSep 27, 2025
polars dataset cannot cast column to Image/Audio/VideoSep 12, 2025
`Sequence(Features(...))` causes PyArrow cast error in `load_dataset` despite correct schema.May 29, 2025
Dataset creation is broken if nesting a dict inside a dict inside a listMay 13, 2025
Nested Feature raises ArrowNotImplementedError: Unsupported cast using function cast_structApr 7, 2025
Timeline
First reported:Apr 7, 2025
Last reported:Sep 27, 2025