isidentical commented on issue #3898:
URL: 
https://github.com/apache/arrow-datafusion/issues/3898#issuecomment-1297564476

   A general overview of what happened during the discussions (in regards to 
the expression analysis part) and the meetup:
   
   - Better value distributions rather than just knowing the `[min, max]`.
   
   Although there isn't any concrete work, this was also part of the proposed 
'future' section and we might be able to turn it into a reality once we have 
the general system ready (this is what Spark did IIRC, they initially 
implemented with basic ranges and then moved over with histograms when 
available).
   
   - Support for comparing two expressions (`a > b`) with different ranges. 
   
   This can be supported with the existing framework, but actually needs an 
implementation 😇 Currently for binary expressions, we have a code path that is 
taken when we know either side has a scalar boundary (e.g. `a=[20, 20]; b=[10, 
30]`) but we can introduce a second one very easily depending on how it would 
work 👀  Requires further research, but I don't think it needs to block this 
ticket (it can actually be a part of it).
   
   - Not passing a mutable handle for the context but rather giving it up 
completely.
   
   I'd be fine with this though just from a purely aesthetic point of view it 
looks a bit hard to parse 😄 I'm happy to be convinced though. Let's discuss it 
in the code review again!


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