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Polars users keep filing bugs

Data engineering10 posts from 8 people7d active+00 posts in the last 7 days, 1 the 7 days before (fading)

Posts per day

Posts per day10 posts, Aug 27 to Sep 25

The posts behind it

10, newest first
PostDate
Add ARRAY_VALUE SQL constructor for fixed-size Arrays### Description SQL can use existing fixed-size Array columns, but cannot construct fixed-size Arrays from row expressions **Reproducer** **Output** **Expected** **Scope** - Require one or more expressions - Set Array width from argument count - Cast arguments to common child...pola-rs/polars0guban0vSep 1213 days ago
Infinite recursion on `log()` on struct### Checks - [x] I have checked that this issue has not already been reported. - [x] I have confirmed this bug exists on the [latest version](https://pypi.org/project/polars/) of Polars. ### Reproducible example ### Log output ### Issue description Segfaults, due to infinite...pola-rs/polarskdn36Sep 72 weeks ago
`Series.slice` function behaves incorrectly (vs `slice` as an expression)### Checks - [x] I have checked that this issue has not already been reported. - [x] I have confirmed this bug exists on the [latest version](https://pypi.org/project/polars/) of Polars. ### Reproducible example ### Log output ### Issue description the `series.slice(-5)` call...pola-rs/polarsadienesSep 62 weeks ago
perf: when loading DataFrame from iterable, chunk_size can be determined more optimally### Description https://github.com/pola-rs/polars/blob/fec681c8a8c4f83ceb4e16c64c2dc4f4a3c1aedf/py-polars/src/polars/_utils/construction/dataframe.py#L1031-L1035 If the schema, if `schema` is provided use `adaptive_chunk_size or 1000`, otherwise `infer_schema_length`.pola-rs/polarslscheillingSep 43 weeks ago
User guide: CSV page has no example reading from a URL or with real data...in both the Python and Rust source files. I can verify the Python side, but I have no way to compile and verify the Rust equivalent (HTTP CSV needs the `cloud` feature), so my draft adds the section as a plain fenced Python block outside the macro system. Happy to do it either...pola-rs/polarsshiftdylson1Sep 43 weeks ago
More (efficient) `Map` operationsWe are missing some key operations like `.map.get(k)` in DSL. The issue is that this, in and of itself, is not efficiently implementable, because we just store the map entries in the input order. So, we would need to rethink how we store a map. Some possibilities are: - Have an...pola-rs/polarsdancsiSep 33 weeks ago
GPU support for `Map`Some functionality in `crates/polars-python/src/lazyframe/visitor/expr_nodes.rs` just returns `Err` for `Map`s, even though the equivalent functionality for `List(Struct)` is already there. It might require some changes in `cuDF` though.pola-rs/polarsdancsiSep 33 weeks ago
Cache `CloudType:HTTP` `ObjectStore`### Description Object store ends up constructing `rustls_native_certs::load_native_certs`, which takes around ~150ms on my Mac. Supposedly a little shorter on Linux. We cache the object store for cloud storage providers and HDFS, why not for HTTP?...pola-rs/polarsEndPositiveSep 23 weeks ago
Segfault on `exp()` on struct### Checks - [x] I have checked that this issue has not already been reported. - [x] I have confirmed this bug exists on the [latest version](https://pypi.org/project/polars/) of Polars. ### Reproducible example ### Log output ### Issue description Segfault when calling `exp()`...pola-rs/polarskdn36Sep 23 weeks ago
Add `LazyFrame.optimize` / `LazyFrame.resolve`### Description As shown by #25246 (and AFAIK it has been requested many more times), it would be relatively useful to be able to cache the optimization or perform optimization in parts. Together with #29003, it should allow a suitable solution for #25246. Implementation-wise,...pola-rs/polarscoastalwhiteAug 274 weeks ago

Companies and products named

Company or productPosts naming it
Polars10
GitHub3
PyPI3
About this problem

Evidence

10 posts from 8 people in 1 place, about 3 a week over 17 days. Mostly on pola-rs/polars. Tools named alongside: GitHub, PyPI.

Frustration Frustration 0 of 3· Seen on GitHub issues

How it was grouped

Posts about Polars that state a pain but match no known issue yet. First post Aug 27, 2026, latest Sep 12, 2026. Corroborated: 3 or more posts from 2 or more people or places. Method

History

  • 2026-09-25 Statement: Polars users keep asking for help to Polars users keep filing bugs
  • 2026-09-25 Added: Polars users keep asking for help (10 posts)

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