Data and AI struggles

1,730 problems · 342 companies

Data engineering

Trouble with Polars list

1 post from 1 person1d activeFading, +0 this weekunverified

Posts per day

Posts per day1 posts, Oct 21 to Nov 9

The posts behind it

GitHub issuespola-rs/polars · lukew-cogappOct 21

Strict construction of `List(Float64)` fails on whole numbers

### 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 schema declares...

1 reactions1 replies

Companies and products named

1 post
1 post
About this problem

Evidence

1 post from 1 person in 1 place. Mostly on pola-rs/polars. Tools named alongside: Elasticsearch, PyPI.

Frustration Frustration 0 of 3· Seen on GitHub issues

How it was grouped

Posts about Polars with no known issue, sharing the word "list". First post Oct 21, 2026, latest Oct 21, 2026. Unverified: fewer than 3 posts, or one person or place only. Method

Other Polars problems

Polars upgrades break working setups

23 posts from 16 people on GitHub issues.

Polars users keep filing bugs

Top post: "Consider upgrading the brotli crate (CVE-2026-111497)", one of 22 posts from 15 people on GitHub issues.

Trouble with Polars column

Top post: "Compare lists in one column to the first n elements of another column in Python Polars lazyframes, where n is", one of 20 posts from 16 people on GitHub issues, Stack Overflow.

Trouble with Polars parquet

Top post: "`is_in` with more than 100 values does not skip Parquet row groups between the values", one of 7 posts from 7 people on GitHub issues.

Trouble with Polars unique

Top post: "Streaming engine: multi-column `.unique()` in `group_by().agg()` much slower than in-memory", one of 7 posts from 4 people on GitHub issues.

Trouble with Polars join

Top post: "Coalescing full join on Int32-vs-Int64 keys with `unique` incorrect", one of 6 posts from 6 people on GitHub issues.

Trouble with Polars instead

Top post: "Series.to_list() panics on out-of-range datetimes instead of raising an error", one of 6 posts from 6 people on GitHub issues.

Trouble with Polars group

Top post: "Datetime out-of-range in `group_by_dynamic` streaming engine", one of 4 posts from 3 people on GitHub issues.

Bad data slips through Polars unnoticed

3 posts from 3 people on GitHub issues, Reddit.

Polars runs out of memory

3 posts from 3 people on GitHub issues.

Trouble with Polars read

Top post: "`read_database` raises `ImportError` with SQLAlchemy 2.1 when `greenlet` is not installed", one of 3 posts from 3 people on GitHub issues.

Polars error messages are cryptic

3 posts from 2 people on GitHub issues.

History

Momentum went from new to fading.

Oct 28, 2026

First seen with 1 post; the top post now: "Strict construction of `List(Float64)` fails on whole numbers".

Oct 24, 2026