tustvold opened a new issue, #5523:
URL: https://github.com/apache/arrow-rs/issues/5523

   **Is your feature request related to a problem or challenge? Please describe 
what you are trying to do.**
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   Currently `RowSelection` stores a list of `RowSelector`. This is optimised 
for the case of large runs of skipped or selected rows, allowing this to be 
pushed down to the underlying decoding machinery. Whilst this works very well 
for the use-case of skipping data based on the page index, where the selections 
are necessarily in the thousands of rows, it will potentially degrade in the 
presence of more granular predicate evaluation, e.g. as performed by 
`ArrowPredicate`.
   
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   In a similar vein to https://github.com/apache/arrow-rs/pull/1248, we should 
have different strategies based on the selectivity of the predicate. In 
particular I would like RowSelection to switch between a `RowSelector` approach 
that is pushed down to the underlying readers, and a late evaluation approach 
where it stores a `BooleanBuffer` that is applied to the columns after the fact
   
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