website: add Apache Arrow 26.0.0 blogpost

_posts/2026-10-08-26.0.0-release.md

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+---
+layout: post
+title: "Apache Arrow 26.0.0 Release"
+date: "2026-10-08 00:00:00"
+author: pmc
+categories: [release]
+---
+<!--
+{% comment %}
+Licensed to the Apache Software Foundation (ASF) under one or more
+contributor license agreements.  See the NOTICE file distributed with
+this work for additional information regarding copyright ownership.
+The ASF licenses this file to you under the Apache License, Version 2.0
+(the "License"); you may not use this file except in compliance with
+the License.  You may obtain a copy of the License at
+
+http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+{% endcomment %}
+-->
+
+The Apache Arrow team is pleased to announce the 26.0.0 release. This release
+covers over 3 months of development work and includes [**337 resolved
+issues**][1] on [**403 distinct commits**][2] from [**108 distinct
+contributors**][2]. See the [Install Page](https://arrow.apache.org/install/) to
+learn how to get the libraries for your platform.
+
+The release notes below are not exhaustive and only expose selected highlights
+of the release. Many other bugfixes and improvements have been made: we refer
+you to the [complete changelog][3].
+
+## Community
+
+Since the 25.0.0 release, Kosta Tarasov, Zehua Zou and Tadeja Kadunc have
+been invited to become committers. Jeffrey Vo has been invited to join
+the Project Management Committee (PMC).
+
+Thanks for your contributions and participation in the project!
+
+## Format Notes
+
+The Tensor and SparseTensor IPC messages have been deprecated in the
+specification, and the corresponding C++ APIs for reading and writing them have
+been deprecated as well ([GH-51100](https://github.com/apache/arrow/issues/51100)).
+
+## Arrow Flight RPC Notes
+
+Work on the Flight SQL ODBC driver continued. RPM packages for the driver are now
+built ([GH-47877](https://github.com/apache/arrow/issues/47877)).
+On Windows, the driver is now statically linked ([GH-49538](https://github.com/apache/arrow/issues/49538)).
+
+## C++ Notes
+
+Most of the C++ JSON handling (integration tests, extension type metadata,
+Parquet, Flight SQL ODBC...) has been migrated from RapidJSON to
+[simdjson](https://github.com/simdjson/simdjson) for parsing and to a new
+`JsonWriter` for serialization ([GH-50566](https://github.com/apache/arrow/issues/50566), [GH-50567](https://github.com/apache/arrow/issues/50567) and
+follow-ups).
+
+The Feather reader and writer V1 APIs have been deprecated in favour of the Arrow
+IPC APIs ([GH-49231](https://github.com/apache/arrow/issues/49231)), in line with the corresponding Python and R deprecations.
+
+### CSV
+
+Two new parse options:
+`pad_short_rows` fills in nulls for rows with missing trailing fields
+([GH-50925](https://github.com/apache/arrow/issues/50925)), and `ignore_extra_columns` drops extra fields from rows that have
+more columns than expected ([GH-50967](https://github.com/apache/arrow/issues/50967)).
+
+### Compute
+
+New `remainder` and `modulo` compute functions have been added ([GH-46901](https://github.com/apache/arrow/issues/46901)).
+
+The temporal rounding functions (`floor_temporal`, `ceil_temporal` and
+`round_temporal`) now accept duration inputs ([GH-50395](https://github.com/apache/arrow/issues/50395)).
+
+Hash aggregations now support `string_view` and `binary_view` grouping keys
+([GH-50223](https://github.com/apache/arrow/issues/50223)), and the `unique`, `value_counts` and `dictionary_encode` functions
+now support `float16` inputs ([GH-50512](https://github.com/apache/arrow/issues/50512)).
+
+### File Systems
+
+**Breaking change:** the S3 filesystem and its AWS SDK dependency have been moved
+out of `libarrow` into a separate `libarrow_s3` library ([GH-50194](https://github.com/apache/arrow/issues/50194)). This
+reduces the size of `libarrow` for users who do not need S3. C++ users of the S3
+filesystem now need to either link against `libarrow_s3` or load it at runtime
+using `LoadFileSystemFactories`.
+
+### Parquet
+
+The schema nesting depth is now limited when parsing the Thrift metadata of a
+Parquet file, turning a stack overflow on pathologically nested schemas into a
+regular error ([GH-51238](https://github.com/apache/arrow/issues/51238)). The default limit (100) can be raised if needed.
+
+Reading Parquet files with unrecognized combinations of logical and physical
+types is now tolerated instead of failing ([GH-50910](https://github.com/apache/arrow/issues/50910)).
+
+A new low-level dense decoding API allows `FIXED_LEN_BYTE_ARRAY` values to be
+decoded directly into caller-provided buffers
+([GH-50333](https://github.com/apache/arrow/issues/50333)).
+
+Reading only the plaintext columns of a partially encrypted Parquet file with a
+plaintext footer no longer fails with a decryption error ([GH-51361](https://github.com/apache/arrow/issues/51361)).
+[GH-51349](https://github.com/apache/arrow/pull/51350) disables reading KMS URLs from file key material by default (`read_kms_url=false`). Applications relying on this behavior should
+ explicitly configure the KMS URL, or opt in with `read_kms_url=true` only if their KMS implementation validates the supplied URL.
+Level histograms written to the Parquet size statistics could be incorrect for
+inputs spanning multiple chunks; this has been fixed ([GH-50778](https://github.com/apache/arrow/issues/50778)).
+
+APIs deprecated in version 23.0.0 and earlier have been removed ([GH-50750](https://github.com/apache/arrow/issues/50750)).
+
+### Miscellaneous C++ changes
+
+`ArrayBuilder` subclasses for binary data now raise a `CapacityError` instead of
+silently truncating values of 2 GiB or more ([GH-51156](https://github.com/apache/arrow/issues/51156)).
+
+Bitmap copy and inversion operations have been sped up, by up to 2x in some
+cases ([GH-50784](https://github.com/apache/arrow/issues/50784)).
+
+The `Datum` class has a new method `ComputeLogicalNullCount` ([GH-50338](https://github.com/apache/arrow/issues/50338)),
+complementing the method added to `ChunkedArray` in the previous release.
+
+## Python Notes
+
+### Compatibility notes
+
+* Python 3.15 is supported and wheels created [GH-48172](https://github.com/apache/arrow/issues/48172).
+* Python 3.10 support dropped [GH-50410](https://github.com/apache/arrow/issues/50410).
+* Support for pandas < 2.2.2 dropped [GH-48808](https://github.com/apache/arrow/issues/48808) and [GH-48473](https://github.com/apache/arrow/issues/48473).
+* We now require numpy 2.x [GH-48473](https://github.com/apache/arrow/issues/48473).
+
+### New features
+
+* Conversion from numpy ` numpy.dtypes.StringDType` to Arrow `string` (also `large_string` or `string_view`) is added [GH-51652](https://github.com/apache/arrow/issues/51652).
+* DLPack implementation now provides export capability for Arrow Arrays, Tensors [GH-39295](https://github.com/apache/arrow/issues/39295) and `FixedShapeTensorArray`/`FixedShapeTensorScalar` [GH-38868](https://github.com/apache/arrow/issues/38868) for consumers implementing DLPack protocol. Also the protocol version has been updated to use version 1.3 [GH-41670](https://github.com/apache/arrow/issues/41670).
+* `record_batch_reader_source` Acero node (`RecordBatchReaderSourceNodeOptions`) is exposed [GH-50801](https://github.com/apache/arrow/issues/50801).
+* `search_sorted` kernel for all primitive types and run-end encoded arrays is available [GH-49677](https://github.com/apache/arrow/issues/49677).
+* `RecordBatchFileReader.count_rows()` binding is added [GH-49305](https://github.com/apache/arrow/issues/49305).
+* `List`, `ListView`, `LargeList`, `LargeListView`, `Map`, `FixedSizeList` and `Struct` values are supported in the `run_end_encode` and the `run_end_decode` paths [GH-44183](https://github.com/apache/arrow/issues/44183).
+* `eol` and `null_string` csv `WriteOptions` have been exposed [GH-34577](https://github.com/apache/arrow/issues/34577).
+
+### Other improvements
+
+* `.slice` methods accept Arrow integer scalars [GH-51145](https://github.com/apache/arrow/issues/51145).
+* `arrow_to_pandas` `DateOffset` handling for nanoseconds/microseconds is simplified [GH-50464](https://github.com/apache/arrow/issues/50464).
+* First step towards abi3 wheels support for pyarrow has been merged [GH-50431](https://github.com/apache/arrow/issues/50431).
+* `is_nested` now uses C++ type traits [GH-40282](https://github.com/apache/arrow/issues/40282).
+
+### Relevant bug fixes
+
+* Converting `arrow.uuid arrays` and `table` columns to pandas now returns `uuid.UUID` objects instead of `bytes` [GH-50312](https://github.com/apache/arrow/issues/50312).
+* Scalar arithmetic dunders now return `NotImplemented` instead of raising `TypeError` when the other operand is not a recognized Arrow/NumPy type [GH-49826](https://github.com/apache/arrow/issues/49826).
+* Raise instead of crashing on unopened `MemoryMappedFile().resize()` [GH-51229](https://github.com/apache/arrow/issues/51229).
+* Writer options are synced between `write_table` and `write_to_dataset`/`ParquetFileFormat.make_write_options(...)` [GH-51220](https://github.com/apache/arrow/issues/51220).
+* `BufferReader.readinto()` segfaults on a read-only destination are fixed [GH-51044](https://github.com/apache/arrow/issues/51044).
+* `FunctionOptions.deserialize()` segfaults on non-buffer arguments are fixed [GH-51041](https://github.com/apache/arrow/issues/51041).
+* Correct type of `ParquetLogicalType` is now returned for Geometry/Geography [GH-50849](https://github.com/apache/arrow/issues/50849).
+* `pa.types.is_nested()` now returns `True` for run-end encoded types [GH-50847](https://github.com/apache/arrow/issues/50847).
+* The reference cycle between the C++ FlightServerBase and the Python object now breaks to avoid leaking the server [GH-50684](https://github.com/apache/arrow/issues/50684).
+* Reference leak in `ConvertToSequenceAndInferSize` when an iterator raises on array conversion is fixed [GH-50591](https://github.com/apache/arrow/issues/50591).
+* `pa.Table.from_struct_array` failure on empty array is fixed [GH-48344](https://github.com/apache/arrow/issues/48344).
+* Invalid operator error message in `pyarrow.parquet` is fixed [GH-47369](https://github.com/apache/arrow/issues/47369).
+* Preserving leading zeros in `read_csv` is now better documented [GH-46853](https://github.com/apache/arrow/issues/46853).
+* `write_dataset` with csv file format ignoring delimiter is fixed [GH-39961](https://github.com/apache/arrow/issues/39961).
+* `pyarrow.array` silently rewriting dictionary types to use signed integers for indexes is fixed [GH-37476](https://github.com/apache/arrow/issues/37476).
+* Extension types with list-based storage cast segfault is fixed [GH-37004](https://github.com/apache/arrow/issues/37004).
+
+## R Notes
+- register_scalar_function() now errors if named fields in in_type do not match the corresponding
+argument names of fun (after the initial context argument), instead of silently ignoring those names ([GH-37761](https://github.com/apache/arrow/pull/51324)).
+### Breaking changes
+
+- `read_feather()` and `write_feather()` are deprecated in favour of `read_ipc_file()` and `write_ipc_file()`, and `format = "feather"` in `open_dataset()` and `write_dataset()` is deprecated in favour of `format = "ipc"` ([GH-49237](https://github.com/apache/arrow/issues/49237)).
+- The long-deprecated `.data.frame` argument to `map_batches()` has been removed, and the planned change to `pull()` returning a `ChunkedArray` by default has been dropped, so `pull()` no longer warns ([GH-51655](https://github.com/apache/arrow/issues/51655)).
+
+### New features
+
+- Azure Blob Storage is now supported via the new `AzureFileSystem` class and `az_container()` helper, analogous to `S3FileSystem` and `s3_bucket()` (@marberts, [GH-32123](https://github.com/apache/arrow/issues/32123)).
+
+### Minor improvements and fixes
+
+- A number of dplyr fixes: variables sharing a name with a function such as `date` now work in verbs ([GH-39688](https://github.com/apache/arrow/issues/39688)), `if_else()` works with a bare `NA` branch alongside dates ([GH-38358](https://github.com/apache/arrow/issues/38358)), and `summarise()` after `arrange()` no longer errors ([GH-45373](https://github.com/apache/arrow/issues/45373)).
+- Factors and integer types inside list columns are now unified across the whole column when reading in multiple batches ([GH-50514](https://github.com/apache/arrow/issues/50514)), and Parquet `float16` columns now read correctly ([GH-50378](https://github.com/apache/arrow/issues/50378)).
+
+
+## Ruby and C GLib Notes
+
+- Flight RPC: Fixed GC related problems: [GH-50401](https://github.com/apache/arrow/pull/50401)
+- Apache Parquet: Added support for buffered reader properties: [GH-51277](https://github.com/apache/arrow/pull/51277)
+
+### Ruby
+
+- red-arrow-format: Added support for building Apache Arrow data from Ruby objects.
+- red-arrow-format: Added support for comparing arrays.
+- red-arrow-format: Added support for comparing types.
+- red-arrow-format: Added support for getting Ruby objects from Apache Arrow data.
+
+### C GLib
+
+No C GLib only notes.
+
+## Java, JavaScript, Go, .NET, Swift and Rust Notes
+
+The Java, JavaScript, Go, .NET, Swift and Rust projects have moved to separate
+repositories outside the main Arrow [monorepo](https://github.com/apache/arrow).
+
+- For notes on the latest release of the [Java
+implementation](https://github.com/apache/arrow-java), see the latest [Arrow
+Java changelog][7].
+- For notes on the latest release of the [JavaScript
+implementation](https://github.com/apache/arrow-js), see the latest [Arrow
+JavaScript changelog][8].
+- For notes on the latest release of the [Rust
+  implementation](https://github.com/apache/arrow-rs) see the latest [Arrow Rust
+  changelog][5].
+- For notes on the latest release of the [Go
+implementation](https://github.com/apache/arrow-go), see the latest [Arrow Go
+changelog][6].
+- For notes on the latest release of the [.NET
+implementation](https://github.com/apache/arrow-dotnet), see the latest [Arrow  .NET changelog][9].
+- For notes on the latest release of the [Swift implementation](https://github.com/apache/arrow-swift), see the latest [Arrow Swift changelog][10].
+
+[1]: https://github.com/apache/arrow/milestone/75?closed=1
+[2]: {{ site.baseurl }}/release/26.0.0.html#contributors
+[3]: {{ site.baseurl }}/release/26.0.0.html#changelog
+[4]: {{ site.baseurl }}/docs/r/news/
+[5]: <https://github.com/apache/arrow-rs/blob/main/CHANGELOG.md>
+[6]: <https://github.com/apache/arrow-go/releases>
+[7]: <https://github.com/apache/arrow-java/releases>
+[8]: <https://github.com/apache/arrow-js/releases>
+[9]: <https://github.com/apache/arrow-dotnet/releases>
+[10]: <https://github.com/apache/arrow-swift/releases>