# Polars 1.1.0 — Python Polars 1.1.0

- Product: Polars (https://whatsnew.fyi/product/polars)
- Vendor: Polars
- Date: 2024-07-07
- Version: 1.1.0
- Original notes: https://github.com/pola-rs/polars/releases/tag/py-1.1.0
- Permalink: https://whatsnew.fyi/product/polars/releases/1.1.0

What's New is an index, not a publisher: every entry below links to the vendor's own release notes, which are the authoritative source. Entries are labelled where they are hand-curated sample data, pre-releases, or drawn from a secondary source such as a developer blog.

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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- **changed** — Keep more parallelism when CSE plan cache hits
- **changed** — Batch parquet primitive decoding
- **changed** — Respect allow_threading in some more operators
- **changed** — Parallelize parquet metadata deserialization
- **changed** — Use underlying fileno for Python files when possible
- **added** — Add future arg to Series.to_arrow
- **added** — Add future versioning
- **changed** — Apply slice pushdown immediately to in-memory frames
- **added** — Support writing hive partitioned parquet
- **added** — Add right join support
- **added** — Support hive partitioning in scan_ipc
- **changed** — Improve error message when passing string key to Series.__getitem__
- **fixed** — Handle DB cursor descriptions that contain more fields than the DBAPI2 standard
- **fixed** — Fix decimal dyn float supertype
- **fixed** — Verify the integrity of pandas column names before implied string conversion
- **fixed** — Don't rechunk on phys_repr
- **fixed** — Harden alchemy session for old sqlalchemy versions
- **fixed** — Fix swapping rename schema
- **fixed** — Make boolean reads consistent across all read_excel engines
- **fixed** — Raise on oob decimal precision

##### 🚀 Performance improvements

- Keep more parallelism when CSE plan cache hits (#17463)
- Batch parquet primitive decoding (#17462)
- Respect allow\_threading in some more operators (#17450)
- Parallelize parquet metadata deserialization (#17399)
- Use underlying fileno for Python files when possible (#17315)
- Add future arg to Series.to\_arrow (#17371)

##### ✨ Enhancements

- Add "future" versioning (#17421)
- Apply slice pushdown immediately to in-memory frames (#17459)
- Support writing hive partitioned parquet (#17324)
- Add right join support (#17441)
- Support hive partitioning in `scan_ipc` (#17434)
- Improve error message when passing string key to `Series.__getitem__` (#17408)

##### 🐞 Bug fixes

- Handle DB cursor descriptions that contain more fields than the DBAPI2 standard (#17468)
- Fix decimal dyn float supertype (#17464)
- Verify the integrity of pandas column names before implied string conversion (#17433)
- Don't rechunk on phys\_repr (#17461)
- Harden alchemy session for old sqlalchemy versions (#17366)
- Fix swapping rename schema (#17458)
- Make boolean reads consistent across all `read_excel` engines (#17448)
- Raise on oob decimal precision (#17445)
- Fix handling of TextIOWrapper in write\_csv (#17328)
- Support sa session (#17435)
- Fix `from_pandas` for string columns with missing values (#17397)
- Fix a global variable table-discovery edge case for the `SQL` interface (#17400)
- Don't allow json inference method to be chunked/streaming (#17396)
- Set literal nesting to 0 (#17392)
- Fix scanning cloud paths with spaces (#17379)
- Fix `slice` length no longer allowing `None` (#17372)
- Fix typo in `SchemaError` exception message (#17350)
- Raise proper error for mismatching parquet schema instead of panicking (#17321)

##### 📖 Documentation

- Add examples for scanning hive datasets to user guide (#17431)
- Update `partition_by` docstring to match new behavior (#17394)
- Update `GroupBy.__iter__` docstring to match new behavior (#17383)

##### 📦 Build system

- Add support for NumPy 2.0 (#17384)

##### 🛠️ Other improvements

- Add automated check for PR title formatting (#17412)
- Remove transmute for object store path (#17395)
- Fix Python version resolver in release drafter (#17390)
- Avoid use of `np.trapz` in tests to prepare for NumPy 2.0 (#17387)
- Avoid writing to disk when running `sink_csv` test (#17386)

Thank you to all our contributors for making this release possible!
@alexander-beedie, @brunobbaraujo, @cmdlineluser, @coastalwhite, @dependabot, @dependabot[bot], @nameexhaustion, @orlp, @phi-friday, @ritchie46, @ruihe774, @sherlockbeard, @stinodego, @tylerriccio33 and @wence-