asolimando commented on PR #22343: URL: https://github.com/apache/datafusion/pull/22343#issuecomment-4485829535
> Perhaps this kind of reordering could be implemented as a runtime optimization inside `FilterExec`: for the first batch, track each conjunct's evaluation time and selectivity, then decide the order dynamically. One nice benefit of this approach is that we don't have to hardcode whether an expression is "expensive" or "cheap". I think it's still useful to be able to re-order "statically" as you might want to use statistics for that, which might be more stable then dynamic approaches, which are usually sensitive to the "shape" of the first part of the data, and the choice is usually not revisited (and even in that case, it might fluctuate, while in some cases the static order could be the optimal one). I think it's good to have multiple options, as long as downstream users can mix and match what works best for them, and they can "easily" correct course for problematic queries without the need of code changes. -- 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]
