ametel01 commented on PR #23038: URL: https://github.com/apache/datafusion/pull/23038#issuecomment-4835975340
hanks @alamb , that makes sense. I agree the physical execution semantics are weak: with no input arrays, a generic accumulator does not have row cardinality, and disabling `convert_to_state` makes the feature much less useful for normal multi-stage aggregate plans. Given that, I think this PR may be the wrong abstraction for #16453. Your struct-returning aggregate suggestion seems like a better direction: model the operation as an aggregate that receives the relevant input columns, for example `augmented_avg(ts, value)`, and returns a struct containing window metadata plus the aggregate result. That keeps the aggregate connected to real input data and avoids adding nullary special cases across the aggregate execution paths. Unless you think there is still independent value in nullary aggregate UDF support, I can close this PR and instead explore/prototype the struct-returning aggregate approach for #16453. -- 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]
