Update here is I have created a PR with example variant values (not yet parquet files, just the variant values)[1].
Since Spark seems to be the only open source software capable of creating variants at this time, I generated the examples using Spark. Please check it out and let me know what you think. If it is acceptable I can work on PRs (based on Aihua's example) for actual parquet files with encoded values Andrew [1]: https://github.com/apache/parquet-testing/pull/76 On Tue, Apr 8, 2025 at 5:46 AM Andrew Lamb <andrewlam...@gmail.com> wrote: > Thank you very much > > On Mon, Apr 7, 2025 at 5:10 PM Aihua Xu <aihu...@gmail.com> wrote: > >> I attached in the https://github.com/apache/parquet-testing/issues/75. >> Please rename them back to *.parquet so you can use parquet tools to view >> them. >> >> I captured them when working on the Iceberg tests in >> >> https://github.com/apache/iceberg/blob/main/parquet/src/test/java/org/apache/iceberg/parquet/TestVariantWriters.java#L172 >> . >> >> You can change to OutputFile outputFile = >> Files.localOutput("primitive.parquet"); to capture them, but you probably >> can follow what David mentioned. >> >> On Mon, Apr 7, 2025 at 12:26 PM Andrew Lamb <andrewlam...@gmail.com> >> wrote: >> >> > Attaching them on the ticket[1] would also be a way to share them >> > >> > It would also be super helpful to share the commands you ran >> > >> > Andrew >> > >> > [1]: https://github.com/apache/parquet-testing/issues/75 >> > >> > On Mon, Apr 7, 2025 at 2:46 PM Adrian Garcia Badaracco >> > <adr...@pydantic.dev.invalid> wrote: >> > >> > > Yes I am not able to see them. Could you make a PR to the repo, or >> upload >> > > them somewhere so we can make a PR? Even if it doesn’t get merged >> > > immediately we can pull them from the PR. Thanks! >> > > >> > > On Mon, Apr 7, 2025 at 1:44 PM Aihua Xu <aihu...@gmail.com> wrote: >> > > >> > > > Hi Adrian, >> > > > >> > > > I attached them to my reply and I'm not sure if the files get >> filtered. >> > > Let >> > > > me know if you still can't see them. Maybe I should push to the repo >> > > > instead. >> > > > >> > > > On Mon, Apr 7, 2025 at 10:58 AM Adrian Garcia Badaracco >> > > > <adr...@pydantic.dev.invalid> wrote: >> > > > >> > > > > Amazing Aihua, thanks so much! >> > > > > >> > > > > Sorry if I just missed it but... where are the files you created? >> I >> > > don't >> > > > > see them in the repo / issue / this thread. >> > > > > >> > > > > On Mon, Apr 7, 2025 at 12:54 PM Aihua Xu <aihu...@gmail.com> >> wrote: >> > > > > >> > > > > > I have created some test files attached during the development, >> one >> > > is >> > > > > > without shredding and one is with shredding. >> > > > > > >> > > > > > As David pointed out, it's missing the Variant logical type but >> > you >> > > > can >> > > > > > use that as reference and as a start. >> > > > > > >> > > > > > On Mon, Apr 7, 2025 at 3:50 AM Andrew Lamb < >> andrewlam...@gmail.com >> > > >> > > > > wrote: >> > > > > > >> > > > > >> I filed a ticket to track this work[1] and also perhaps to >> gather >> > > some >> > > > > >> additional help / collaboration. >> > > > > >> >> > > > > >> [1]: https://github.com/apache/parquet-testing/issues/75 >> > > > > >> >> > > > > >> On Mon, Apr 7, 2025 at 6:02 AM Andrew Lamb < >> > andrewlam...@gmail.com> >> > > > > >> wrote: >> > > > > >> >> > > > > >> > Thank you very much David >> > > > > >> > >> > > > > >> > I will try to create some examples this week and report back. >> > > > > >> > >> > > > > >> > Andrew >> > > > > >> > >> > > > > >> > On Sun, Apr 6, 2025 at 4:48 PM David Cashman >> > > > > >> > <david.cash...@databricks.com.invalid> wrote: >> > > > > >> > >> > > > > >> >> Hi Andrew, you should be able to create shredded files using >> > OSS >> > > > > Spark >> > > > > >> >> 4.0. I think the only issue is that it doesn't have the >> logical >> > > > type >> > > > > >> >> annotation yet, so readers wouldn't be able to distinguish >> it >> > > from >> > > > a >> > > > > >> >> non-variant struct that happens to have the same schema. >> (Spark >> > > is >> > > > > >> >> able to infer that it is a Variant from the >> > > > > >> >> `org.apache.spark.sql.parquet.row.metadata` metadata.) >> > > > > >> >> >> > > > > >> >> The ParquetVariantShreddingSuite in Spark has some tests >> that >> > > write >> > > > > >> >> and read shredded parquet files. Below is an example that >> > > > translates >> > > > > >> >> the first test into code that runs in spark-shell and >> writes a >> > > > > Parquet >> > > > > >> >> file. The shredding schema is set via conf. If you want to >> test >> > > > types >> > > > > >> >> that Spark doesn't infer in parse_json (e.g. timestamp, >> > binary), >> > > > you >> > > > > >> >> can use `to_variant_object` to cast structured values to >> > Variant. >> > > > > >> >> >> > > > > >> >> I won't have time to work on this in the next couple of >> weeks, >> > > but >> > > > am >> > > > > >> >> happy to answer any questions. >> > > > > >> >> >> > > > > >> >> Thanks, >> > > > > >> >> >> > > > > >> >> David >> > > > > >> >> >> > > > > >> >> scala> import org.apache.spark.sql.internal.SQLConf >> > > > > >> >> scala> >> > > spark.conf.set(SQLConf.VARIANT_WRITE_SHREDDING_ENABLED.key, >> > > > > >> true) >> > > > > >> >> scala> >> > spark.conf.set(SQLConf.VARIANT_ALLOW_READING_SHREDDED.key, >> > > > > true) >> > > > > >> >> scala> >> > > > > >> >> > spark.conf.set(SQLConf.VARIANT_FORCE_SHREDDING_SCHEMA_FOR_TEST.key, >> > > > > >> >> "a int, b string, c decimal(15, 1)") >> > > > > >> >> scala> val df = spark.sql( >> > > > > >> >> | """ >> > > > > >> >> | | select case >> > > > > >> >> | | when id = 0 then parse_json('{"a": 1, "b": >> > "2", >> > > > "c": >> > > > > >> >> 3.3, "d": 4.4}') >> > > > > >> >> | | when id = 1 then parse_json('{"a": [1,2,3], >> > "b": >> > > > > >> >> "hello", "c": {"x": 0}}') >> > > > > >> >> | | when id = 2 then parse_json('{"A": 1, "c": >> > > 1.23}') >> > > > > >> >> | | end v from range(3) >> > > > > >> >> | |""".stripMargin) >> > > > > >> >> scala> >> df.write.mode("overwrite").parquet("/tmp/shredded_test") >> > > > > >> >> scala> spark.read.parquet("/tmp/shredded_test").show >> > > > > >> >> +--------------------+ >> > > > > >> >> | v| >> > > > > >> >> +--------------------+ >> > > > > >> >> |{"a":1,"b":"2","c...| >> > > > > >> >> |{"a":[1,2,3],"b":...| >> > > > > >> >> | {"A":1,"c":1.23}| >> > > > > >> >> +--------------------+ >> > > > > >> >> >> > > > > >> >> >> > > > > >> >> On Sun, Apr 6, 2025 at 2:54 PM Andrew Lamb < >> > > andrewlam...@gmail.com >> > > > > >> > > > > >> >> wrote: >> > > > > >> >> > >> > > > > >> >> > Can someone (pretty pretty) please give us some binary >> > examples >> > > > so >> > > > > we >> > > > > >> >> can >> > > > > >> >> > make faster progress on the Rust implementation? >> > > > > >> >> > >> > > > > >> >> > We recently got exciting news[1] that folks from the CMU >> > > database >> > > > > >> group >> > > > > >> >> > have started working on the Rust implementation of >> variant, >> > > and I >> > > > > >> would >> > > > > >> >> > very much like to encourage and support their work. >> > > > > >> >> > >> > > > > >> >> > I am willing to do some legwork (make a PR to >> parquet-testing >> > > for >> > > > > >> >> example) >> > > > > >> >> > if someone can point me to the files (or instructions on >> how >> > to >> > > > use >> > > > > >> some >> > > > > >> >> > system to create variants). >> > > > > >> >> > >> > > > > >> >> > I was hoping that since the VARIANT format[2] and draft >> > > shredding >> > > > > >> >> spec[3] >> > > > > >> >> > have been in the repo for 6 months (since October 2024) , >> it >> > > > would >> > > > > be >> > > > > >> >> > straightforward to provide some examples. Do we know >> anything >> > > > that >> > > > > is >> > > > > >> >> > blocking the creation of examples? >> > > > > >> >> > >> > > > > >> >> > Andrew >> > > > > >> >> > >> > > > > >> >> > [1]: >> > > > > >> >> >> > > > > >> > https://github.com/apache/arrow-rs/issues/6736#issuecomment-2781556103 >> > > > > >> >> > [2]: >> > > > > >> >> >> > > > > >> >> > > > >> > https://github.com/apache/parquet-format/blob/master/VariantEncoding.md >> > > > > >> >> > [3]: >> > > > > >> >> > >> > > > > >> >> >> > > > > >> >> > > > > >> > > >> https://github.com/apache/parquet-format/blob/master/VariantShredding.md >> > > > > >> >> > >> > > > > >> >> > >> > > > > >> >> > On Wed, Mar 5, 2025 at 3:58 PM Julien Le Dem < >> > > jul...@apache.org> >> > > > > >> wrote: >> > > > > >> >> > >> > > > > >> >> > > That sounds like a great suggestion to me. >> > > > > >> >> > > >> > > > > >> >> > > On Wed, Mar 5, 2025 at 12:41 PM Andrew Lamb < >> > > > > >> andrewlam...@gmail.com> >> > > > > >> >> > > wrote: >> > > > > >> >> > > >> > > > > >> >> > > > I would like to request before the VARIANT spec >> changes >> > are >> > > > > >> >> finalized >> > > > > >> >> > > that >> > > > > >> >> > > > we have example data in parquet-testing. >> > > > > >> >> > > > >> > > > > >> >> > > > This topic came up (well, I brought it up) on the sync >> > call >> > > > > >> today. >> > > > > >> >> > > > >> > > > > >> >> > > > In my opinion, having example files would reduce the >> > > overhead >> > > > > of >> > > > > >> new >> > > > > >> >> > > > implementations dramatically. At least there should be >> > > > example >> > > > > of >> > > > > >> >> > > > * variant columns (no shredding) >> > > > > >> >> > > > * variant columns with shredding >> > > > > >> >> > > > >> > > > > >> >> > > > Some description of what those files contained >> ("expected >> > > > > >> >> contents"). For >> > > > > >> >> > > > prior art, here is what Dewey did for the geometry >> > > > type[1][2]. >> > > > > >> >> > > > >> > > > > >> >> > > > When looking for prior discussions, I found a great >> quote >> > > > from >> > > > > >> Gang >> > > > > >> >> Wu[3] >> > > > > >> >> > > > on this topic: >> > > > > >> >> > > > >> > > > > >> >> > > > > I'd say that a lesson learned is that we should >> > publish >> > > > > >> example >> > > > > >> >> files >> > > > > >> >> > > > for any >> > > > > >> >> > > > > new feature to the parquet-testing [1] repo for >> > > > > >> interoperability >> > > > > >> >> tests. >> > > > > >> >> > > > >> > > > > >> >> > > > Thank you for your consideration, >> > > > > >> >> > > > Andrew >> > > > > >> >> > > > >> > > > > >> >> > > > >> > > > > >> >> > > > >> > > > > >> >> > > > >> > > > > >> >> > > > [1] https://github.com/apache/parquet-testing/pull/70 >> > > > > >> >> > > > [2] https://github.com/geoarrow/geoarrow-data >> > > > > >> >> > > > [3]: >> > > > > >> >> >> > https://lists.apache.org/thread/71d7p9lprhf514jnt5dgnw4wfmn8ykzt >> > > > > >> >> > > > >> > > > > >> >> > > >> > > > > >> >> >> > > > > >> > >> > > > > >> >> > > > > > >> > > > > >> > > > >> > > >> > >> >
