Problemsby GlyphTrouble with Polars join
6 posts from 6 people6d activeFading, +0 this week
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The posts behind it
perf: `join_where(how="left")` with an equality predicate uses a nested loop join (quadratic)
...because the comparison there wasn't equivalent (it duplicated unmatched left rows). The workaround above handles that case correctly, which shows the slowdown isn't inherent to left-join semantics. ### Expected behavior When the predicates contain at least one equality between...
Support subqueries in join clauses (SQL)
### Description Expanding on https://github.com/pola-rs/polars/issues/30120 , 33 of the first 300 SQLStorm TPC-H queries fail due to subqueries being rejected in joins:
Coalescing full join on Int32-vs-Int64 keys with `unique` incorrect
### 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 See repro. Note, in-memory...
Add `asof_join()` functionality for SQL
### Description Tried to perform an asof join on the new release. Not seeing any documentation on the SQL page, I tried the following:
In streaming mode, `.limit()` doesn't return early after join operations
### 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 When doing a join between two...
Left join using `join_where()` causes rayon stackoverflow
...to perform non-equi left joins between LazyFrames with 10,000,000+ rows but have been unable to perform such a join with `join_where()` outside of relatively very small datasets. I am able to perform standard left joins followed by `filter()` with large datasets. ### Expected...
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About this problem
Evidence
6 posts from 6 people in 1 place, about 1 a week over 63 days. Mostly on pola-rs/polars. Tools named alongside: PyPI, GitHub.
Frustration Frustration 0 of 3· Seen on GitHub issues
How it was grouped
Posts about Polars with no known issue, sharing the word "join". First post Aug 29, 2026, latest Oct 30, 2026. Corroborated: 3 or more posts from 2 or more people or places. Method
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