niyue opened a new pull request, #39046: URL: https://github.com/apache/arrow/pull/39046
### Rationale for this change Acero's union node produce duplicated batch index if having multiple ordered input nodes, which makes down stream nodes unable to process these batches if ordering is a concern. This PR tries to address this issue. ### What changes are included in this PR? This PR fixes this issue by setting the index to unspecified if the order cannot be guaranteed. ### Are these changes tested? Yes ### Are there any user-facing changes? No -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
