Github user vvysotskyi commented on a diff in the pull request:
https://github.com/apache/drill/pull/1068#discussion_r156621897
--- Diff:
exec/java-exec/src/main/java/org/apache/drill/exec/vector/complex/FieldIdUtil.java
---
@@ -131,7 +131,7 @@ public static TypedFieldId
getFieldIdIfMatches(ValueVector vector, TypedFieldId.
} else if(v instanceof ListVector) {
ListVector list = (ListVector) v;
return getFieldIdIfMatches(list, builder, addToBreadCrumb,
seg.getChild());
- } else if (v instanceof UnionVector) {
+ } else if (v instanceof UnionVector && !seg.isLastPath()) {
--- End diff --
Good catch!
I think we should add check for nulls into method
`getFieldIdIfMatchesUnion()` as it was done for `getFieldIdIfMatches()`. Also
please add a unit test for this change. You may use
[testFieldWithDots()](https://github.com/apache/drill/blob/acc5ed927e1fa4011ac1c3724d15197484b9f45b/exec/java-exec/src/test/java/org/apache/drill/exec/vector/complex/writer/TestJsonReader.java#L705)
as an example.
But one more point: with this change error is not thrown, but only nulls
are returned. I think we should also fix this issue on the borders of this pull
request.
---
