# Polars 1.38.1 — Python Polars 1.38.1

- Product: Polars (https://whatsnew.fyi/product/polars)
- Vendor: Polars
- Date: 2026-02-06
- Version: 1.38.1
- Original notes: https://github.com/pola-rs/polars/releases/tag/py-1.38.1
- Permalink: https://whatsnew.fyi/product/polars/releases/1.38.1

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Reuse: the summaries, labels and curation here are © What's New. Quote freely with attribution and a link back; wholesale republication of the corpus is not permitted — terms: https://whatsnew.fyi/terms. The vendors' own release notes remain their publishers'.

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- **added** — Add get() to retrieve a byte from binary data
- **changed** — Remove with_context in SQL lowering
- **fixed** — Do not overwrite used names in cluster_with_columns pushdown
- **fixed** — Do not mark output of concat_str on multiple inputs as sorted
- **fixed** — Fix CSV schema inference content line duplication bug
- **fixed** — Fix InvalidOperationError using scan_delta with filter
- **fixed** — Alias giving missing column after streaming GroupBy CSE
- **fixed** — Ensure by_name selector selects only names
- **fixed** — Restore compatibility of strings written to parquet with pyarrow filter
- **fixed** — Update schema in cluster_with_columns optimization
- **fixed** — Fix negative slice in groups slicing
- **fixed** — Don't run CPU check on aarch64 musl
- **fixed** — Fixed annotations shadowed by class methods
- **fixed** — Fix selector match patterns for multiline column names

##### ✨ Enhancements

- Add get() to retrieve a byte from binary data (#26454)
- Remove with\_context in SQL lowering (#26416)

##### 🐞 Bug fixes

- Do not overwrite used names in cluster\_with\_columns pushdown (#26467)
- Do not mark output of concat\_str on multiple inputs as sorted (#26468)
- Fix CSV schema inference content line duplication bug (#26452)
- Fix InvalidOperationError using `scan_delta` with filter (#26448)
- Alias giving missing column after streaming GroupBy CSE (#26447)
- Ensure `by_name` selector selects only names (#26437)
- Restore compatibility of strings written to parquet with pyarrow filter (#26436)
- Update schema in cluster\_with\_columns optimization (#26430)
- Fix negative slice in groups slicing (#26442)
- Don't run CPU check on aarch64 musl (#26439)
- Fixed annotations shadowed by class methods (#26356)
- Remove the `POLARS_IDEAL_MORSEL_SIZE` monkeypatching in the parametric merge-join test (#26418)
- Fix `selector` match patterns for multiline column names (#26320)

##### 📖 Documentation

- Add `sink_delta` to API reference (#26446)

##### 🛠️ Other improvements

- Cleanup unused attributes in optimizer (#26464)
- Use `Expr::Display` as catch all for IR - DSL asymmetry (#26471)
- Ignore pytz in mypy (#26441)
- Remove the `POLARS_IDEAL_MORSEL_SIZE` monkeypatching in the parametric merge-join test (#26418)
- Cleanup the parametric merge-join test (#26413)

Thank you to all our contributors for making this release possible!
@Voultapher, @alexander-beedie, @azimafroozeh, @cmdlineluser, @dependabot[bot], @dsprenkels, @hamdanal, @kdn36, @nameexhaustion, @orlp, @ritchie46 and [dependabot[bot]](https://github.com/apps/dependabot)