clintropolis opened a new pull request, #15959: URL: https://github.com/apache/druid/pull/15959
### Description Fixes a mistake in expression virtual column indexes, which would incorrectly return `null` from the index supplier, which is a signal to downstream filters that the column is all nulls, even for expressions which translate null values into not null values. This affects filters on stuff like `nvl`, `coalesce`, 3 argument `lookup`, etc. when filtering for the replaced value. The added test would incorrectly fail the 2nd case. <hr> This PR has: - [x] been self-reviewed. - [x] added comments explaining the "why" and the intent of the code wherever would not be obvious for an unfamiliar reader. - [x] added unit tests or modified existing tests to cover new code paths, ensuring the threshold for [code coverage](https://github.com/apache/druid/blob/master/dev/code-review/code-coverage.md) is met. - [x] been tested in a test Druid cluster. -- 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] --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
