[0.8.0] - 2022-11-19#


  • Python 3.11 wheels. (PR #58, contribution of @dbaxa)


  • ORC C++ Core updated to 1.7.7.

  • Improved type annotations, set module’s __all__ variable.

[0.7.0] - 2022-07-16#


  • Universal2 wheels for MacOS. (PR #55, contribution of @dbaxa)

  • ORC-517, ORC-203, and ORC-14 versions to WriterVersion enum.


  • Dropped support for Python 3.6.

  • ORC C++ Core updated to 1.7.5.

[0.6.0] - 2022-02-18#


  • New parameter to Writer: dict_key_size_threshold for setting threshold for dictionary encoding. (PR #46, contribution of @dirtysalt)

  • New parameter to Writer: padding_tolerance for block padding.

  • New parameter to Reader and Writer: null_value for changing representation of ORC null value. The value must be a singleton object.

  • Type stubs for classes implemented in C++.

  • Experimental musllinux and PyPy wheels.


  • Writer.writerows method reimplemented in C++.

  • Improved type annotations.

  • ORC C++ Core updated to 1.7.3.

  • Removed build_orc command, moved the same functionality to build_ext command.


  • Unnecessary string casting of values when writing user metadata. (Issue #45)

[0.5.0] - 2021-10-22#


  • Module level variables for the ORC library version: orc_version string and orc_version_info namedtuple.

  • New parameter for Writer: row_index_stride.

  • New read-only properties for Reader: row_index_stride and software_version.

  • Trino and Scritchley writer ids.

  • Type annotations support for ORC types.

  • Support for timestamp with local time zone type.

  • New parameter for Reader and Writer: timezone.

  • The backported zoneinfo module dependency pior to Python 3.9.

  • Predicate (SearchArgument) support for filtering row groups during ORC file reads. New classes: Predicate and PredicateColumn.

  • New parameter for Reader: predicate.

  • Build for aarch64 wheels. (PR #43, contribution of @odidev)


  • ORC C++ Core updated to 1.7.0, and because many of the new features are not backported to the 1.6 branch, currently this is the minimum required lib version.

  • TimestampConverter’s to_orc and from_orc methods got an extra timezone parameter, that will be bound to the same ZoneInfo object passed to the Reader or Writer via their timezone parameters during type convert.

  • Renamed Reader.metadata property and Writer.set_metadata method to user_metadata and set_user_metadata respectively to avoid confusion.

[0.4.0] - 2021-01-11#


  • Experimental Windows support.

  • tzdata package dependency on Windows. Automatically setting TZDIR to the path of the tzdata package’s data dir after importing PyORC.


  • Create ORC Type from TypeDescription directly (instead of string parsing) for Writer. (PR #26, contribution of @blkerby)

  • Dotted column names are allowed to use in TypeDescription.find_column_id method with escaping them backticks.

  • ORC C++ Core updated to 1.6.6.


  • Handling large negative seconds on Windows for TimestampConverter.from_orc.

[0.3.0] - 2020-05-24#


  • Metadata property for Reader and set_metadata for Writer to handle ORC file’s metadata.

  • Meta info attributes like writer_id, writer_version, bytes_length, compression and compression_block_size for Reader.

  • New TypeDescription subclasses to represent ORC types.


  • Reimplemented TypeDescription in Python.

  • ORC C++ Core updated to 1.6.3.


  • Converting date from ORC on systems where the system’s timezone has a negative UTC offset (Issues #5)

[0.2.0] - 2020-01-01#


  • Converters for date, decimal and timestamp ORC types in Python and option to change them via Reader’s and Writer’s converters parameter.

  • Column object for accessing statistics about ORC columns.

  • An attribute to Reader for selected schema.


  • Use timezone-aware datetime objects (in UTC) for ORC timestamps by default.

  • Wrapped C++ stripe object to Python Stripe.


  • Decrementing reference for bytes object after reading from file stream.

[0.1.0] - 2019-11-16#


  • A Reader object to read ORC files.

  • A stripe object to read only a stripe in an ORC file.

  • A Writer object to write ORC files.

  • A typedescription object to represent the ORC schema.

  • Support to represent a struct type either a Python tuple or a dictionary.