adamreeve opened a new issue, #41140: URL: https://github.com/apache/arrow/issues/41140
### Describe the bug, including details regarding any error messages, version, and platform. Similar to #40790, a sliced union array doesn't behave as expected as none of the methods or properties account for the offset and length. This should work differently for sparse and dense unions. For a sparse union, the child arrays should be sliced when accessed, and the offset and slice should be accounted for in the `TypeIds` span. For a dense union, the child arrays shouldn't be sliced but the `TypeIds` and `ValueOffsets` spans should. ### Component(s) C# -- 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]
