+1 I agree with Neelesh, I believe this will be a major step forward for communicating compatibility across the ecosystem
On Fri, Jul 31, 2026 at 5:13 PM Neelesh Salian <[email protected]> wrote: > +1 (non-binding) > > Thank you for all the work that went into getting this to a good place. > This is a great next step for the community. > > On Fri, Jul 31, 2026 at 14:07 Julien Le Dem <[email protected]> wrote: > > > Hello everyone, > > > > Following questions on the the previous vote > > <https://lists.apache.org/thread/o8bwmqdy1wf0z459h65x43lnsrldrvhq> > thread, > > here is a new vote essentially proposing the same thing but clarifying > the > > specific points raised then. This is the result of our discussions over > the > > last two weeks. With the direction set, we'll work on the linked design > to > > finalize the implementation details. We decided to start a fresh vote to > > remove ambiguity of clarifying while voting is happening. See below. > > > > Julien > > > > This vote is to formalize our intent to use major version numbers to > bundle > > groups of new features in Parquet. This is especially important to enable > > the safe roll-out of forward incompatible features (examples: new > > encodings). We will separately iron out the implementation details in > > the Parquet > > Versioning doc > > < > > > https://docs.google.com/document/d/19bOTy1WcLs9NP88DrysG4wG50pM6gmIFaSEWzkxUeJw/edit?tab=t.0#heading=h.qlhnuhge8ke2 > > > > > based on the principles below. > > > > Goals: > > > > - > > > > Have a clear definition of what is forward compatible or not. > > - > > > > Have a clear definition of what supporting a specific Parquet version > > means (for write and for read). > > - > > > > Have clear version numbers for the ecosystem to coordinate on what’s > > coming in the next version. Pragmatism will prevail by making them not > > too > > frequent but not too far apart. > > - > > > > Ensure new features become mainstream in a reasonable amount of time. > > > > > > Specifically, > > > > - > > > > We will accumulate forward-incompatible changes targeted at the next > > major version of the Parquet spec (for example Version 3). These > > are called “In > > preview” > > - > > > > The same bar applies as before (two implementations, cross-testing, … > > < > > > https://github.com/apache/parquet-format/blob/master/CONTRIBUTING.md#additionschanges-to-the-format > > >) > > to add these features in preview in the spec. > > - > > > > While in preview they can be used for writing with a feature flag, in > > particular to allow integration testing. All implementations are > > encouraged > > to start being able to read it ASAP (at least two distinct OSS > > implementations are already required to reach this stage). > > - > > > > These new changes will automatically go into the next major version. > > (pragmatism applies for exceptions) > > - > > > > We will have a community vote to close and adopt the next major > version. > > - > > > > At this point these features are no longer in preview. Systems > > supporting the new version of Parquet (example: Parquet V3) can start > > using > > it for writing new files by default. (Or communicate what they support > > reading and what they write into files). > > - > > > > In an environment that requires compatibility with at least one system > > that doesn’t support the latest version of Parquet yet, one can pin > to a > > specific version by passing a dedicated option to the writer. > (example, > > support reading Parquet V3 but opt to only write Parquet V2 until the > > environment has upgraded). > > > > > > Please vote in the next 72 hours: > > > > [ ] +1: Adopt versions for forward-incompatible changes > > > > [ ] +0: Not going to block, but prefer . . . > > > > [ ] -1: Do not adopt versions for forward-incompatible changes because . > . > > . > > >
