zhuqi-lucas commented on PR #23369:
URL: https://github.com/apache/datafusion/pull/23369#issuecomment-4924812648

   > > Basically no regression, and it seems resolve the pushdown_filters 
regression, but Adaptive predicate evaluation should be better.
   > 
   > This seems like a very nice find (a simple heuristic) @zhuqi-lucas -- 
would you be willing to make a new PR with just this change? I think we should 
consider doing it.
   > 
   > The heuristic might also want to take into account data type (e.g. 
projecting string columns might count more than projecting an int column)
   > 
   > I would like to run some more tests to see that it works across other 
query benchmarks, but I think we should do it
   
   Thanks @alamb! Yes, let me open a separate PR with just the heuristic gate 
so it can be reviewed and merged on its own, then follow up with the 
pushdown_filters=true default flip once we have the extended benchmark data.
   
   Good call on data-type weighting — I'll experiment with weighting non-filter 
columns by an estimated byte size per row (e.g. Utf8 / Binary / List count much 
more than Int32) so the gate captures the actual wide-decode saving. Will also 
make the threshold configurable so it's tunable per workload if the heuristic 
misfires on someone's data.
   
   I'll post the new PR shortly!


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