Hi John, I believe this is an oversight in the API. I think we should probably open up a JIRA and try to address it.
Depending on the use-case you might be able to write a map as list-of-struct<key, value> and replace the metadata at some point, but I'm not sure if this is possible in the Java library, so I don't have any examples. Thanks, Micah On Fri, Jan 1, 2021 at 10:02 PM John Peterson <[email protected]> wrote: > Hi All, > > I’m attempting to convert the following data structure into vectors for > Arrow: > > Map<String, Map<String, Integer>> > > Using the UnionMapWriter, it seems that I can’t grab a map writer for the > value of the map, but a nested complex type such as a list is supported: > > writer.value().list(); // works, get a ListWriter > writer.value().map(); // doesn’t work, no such method > > Is this a known limitation, or is there a proper way to translate nested > map structures to Arrow? I’m planning on supporting a Map as both a key and > a value of a map. If there is a way to do this (even without the writers), > could you please point me to an example? > > Thanks in advance for your help with this. > > John >
