jacques-n commented on pull request #10934: URL: https://github.com/apache/arrow/pull/10934#issuecomment-907719679
>> I think it would be useful to be able to serialize and send e.g. sum($expr_0) / mean($expr_1) (with these expressions being possibly unbound to a particular table schema) without having to build an aggregation relational operator I'm assuming you mean that you want to avoid having to build a project on top of an aggregate? (please confirm my interprestation of what you said). My initial intuition is that supporting arbitrary expressions in aggregation creates more complexity (and heavier requirement on semantic analysis to confirm plan validity). I agree that there are situations where you might want a compound relational operation that does an aggregation calculation followed immediately by a non-aggregate calculation (e.g. the division in your expression). However, I think that "compound aggregate" would be an additional relational operator we could introduce at a later stage as opposed to being one of the initial primitives (or possibly even be an internal concern/optimization of a particular execution engine). -- 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]
