Problemsby GlyphTrouble with Polars parquet
7 posts from 7 people6d activeFading, +0 this week
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The posts behind it
Parquet writer merges UInt64/UInt32 page statistics with a signed comparison (row-group min > max), so `scan_parquet` filters drop matching rows
### 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 Output: `df.lazy().sink_parquet("u64s.parquet", data_page_size=64)`...
read_parquet(use_pyarrow=True) cannot read a remote directory or a list of remote files
### 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 `read_parquet(source,...
perf: `is_in` with more than 100 values does not skip Parquet row groups between the values
Row-group pruning for `is_in` is exact for up to 100 values (#27475). Above that, a row group is only skipped if it lies entirely outside `[min(values), max(values)]`, so row groups between the values are still read. On really large parquet where you may want to filter row...
Polars List type in sink_parquet discards Pyarrow metadata
### 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 saving a LazyFrame via...
Panic in scan_parquet when filtering on a struct field if the struct contains a Datetime/Date field
### 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 Filtering a scan_parquet on a...
int96 datetimes overflow when casted to microseconds precision during parquet scans
### 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 Reading int96 datetimes...
Custom `pyarrow_options` in `write_parquet` are overwritten by default function args
### 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 Although the User specifically...
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About this problem
Evidence
7 posts from 7 people in 1 place, about 1 a week over 46 days. Mostly on pola-rs/polars. Tools named alongside: PyPI.
Frustration Frustration 0 of 3· Seen on GitHub issues
How it was grouped
Posts about Polars with no known issue, sharing the word "parquet". First post Sep 3, 2026, latest Oct 18, 2026. Corroborated: 3 or more posts from 2 or more people or places. Method
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History