[
https://issues.apache.org/jira/browse/DRILL-8185?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17567780#comment-17567780
]
Paul Rogers commented on DRILL-8185:
------------------------------------
Have found the root cause and am working on a solution. The root cause is that
the HDF5 reader makes use of Drill's problem-child UNION type. This type has
had many problems. It is not at all supported by clients. In this case, we have
an unprojected union, which requires a set of "dummy" mechanisms that acts like
a "real" UNION, but doesn't actually have any backing vectors. Am working
though the the complexities of adding these dummy mechanisms.
HDF5 actually uses the LIST type, which is, essentially, an array of UNIONs
(with all manner of additional complexity). I will have to sort out dummy
vectors for that types as well.
> EVF 2 doen't handle map arrays or nested maps
> ---------------------------------------------
>
> Key: DRILL-8185
> URL: https://issues.apache.org/jira/browse/DRILL-8185
> Project: Apache Drill
> Issue Type: Bug
> Affects Versions: 1.20.0
> Reporter: Paul Rogers
> Assignee: Paul Rogers
> Priority: Major
> Fix For: 2.0.0
>
>
> When converting Avro, Luoc found two bugs in how EVF 2 (the projection
> mechanism) handles map array and nested maps
--
This message was sent by Atlassian Jira
(v8.20.10#820010)
