> > Also does the C++ Parquet to Arrow reader have any such limitations?
The C++ implementation can currently either read nested structs or nested lists but not a combination of the two. It is actively being worked on to be able to handle arbitrary nesting. On Tue, Aug 25, 2020 at 1:15 AM Anoop Johnson <[email protected]> wrote: > If I read the Iceberg vectorized reader code right, it does not support > nested types (same limitation as Spark's built-in vectorized parquet > reader). Is that correct? Also does the C++ Parquet to Arrow reader have > any such limitations? > > On Wed, Aug 19, 2020 at 9:37 AM Jacques Nadeau <[email protected]> wrote: > >> I believe there is code in the iceberg project to do this in pure Java >> [1]. Right now, there isn't a pure java implementation in the Arrow project. >> >> [1] >> https://github.com/apache/iceberg/tree/master/arrow/src/main/java/org/apache/iceberg/arrow/vectorized >> >> On Wed, Aug 19, 2020 at 5:18 AM Chris Nuernberger <[email protected]> >> wrote: >> >>> Also, javacpp has prepackaged C++ bindings to arrow for multiple OS's: >>> >>> http://bytedeco.org/javacpp-presets/arrow/apidocs/ >>> >>> We have had success with javacpp >>> <https://github.com/techascent/tech.opencv> in the past and it is much >>> better now that their preprocess is based on Clang. >>> >>> On Tue, Aug 18, 2020 at 4:16 PM Chris Nuernberger <[email protected]> >>> wrote: >>> >>>> Thanks, that is helpful. >>>> >>>> Chris >>>> >>>> On Tue, Aug 18, 2020 at 10:24 AM Micah Kornfield <[email protected]> >>>> wrote: >>>> >>>>> Hi Chris, >>>>> There is an open PR to support this through C++'s Dataset >>>>> functionality [1]. There was also a prior attempt that went stale and I >>>>> can't find at the moment. >>>>> >>>>> IIUC the main missing component at this point before the PR gets >>>>> merged is integration to honor "-XX:MaxDirectMemorySize" settings. >>>>> >>>>> -Micah >>>>> >>>>> [1] https://github.com/apache/arrow/pull/7030 >>>>> >>>>> >>>>> >>>>> [1] https://github.com/apache/arrow/pull/7030 >>>>> >>>>> On Tue, Aug 18, 2020 at 6:48 AM Chris Nuernberger < >>>>> [email protected]> wrote: >>>>> >>>>>> Hey, >>>>>> >>>>>> We were wondering what the best way to convert a parquet file to an >>>>>> arrow file would be via a java pathway. I notice that the c++ layer >>>>>> appears to have this conversion. >>>>>> >>>>>> The best hint I have see so far is this gist: >>>>>> >>>>>> https://gist.github.com/animeshtrivedi/76de64f9dab1453958e1d4f8eca1605f >>>>>> >>>>>> I also found this jni pathway for ORC files: >>>>>> https://github.com/apache/arrow/tree/master/cpp/src/jni >>>>>> >>>>>> Another thought I had was to use the JNA or JNR and bind to the C >>>>>> glib pathway. >>>>>> >>>>>> Thanks for any help, >>>>>> >>>>>> Chris >>>>>> >>>>>
