alamb opened a new issue, #9961:
URL: https://github.com/apache/arrow-datafusion/issues/9961

   ### Is your feature request related to a problem or challenge?
   
   @appletreeisyellow  added `PruningStatistics::row_counts()` in 
https://github.com/apache/arrow-datafusion/pull/9223 which allows better 
pruning of columns which are all null.
   
   However, I believe we have not hooked that API up into the `ParquetExec`, so 
it won't prune row groups based on this information.
   
   
   For example, if column `a` is all NULL, a predicate `a > 5' can never be 
true, but the  the ParquetExec won't be able to prune row groups or pages for 
this case
   
   ### Describe the solution you'd like
   
   Implement `RowGroupPruningStastics::row_counts`
   
   
https://github.com/apache/arrow-datafusion/blob/2dad90425bacb98a3c2a4214faad53850c93104e/datafusion/core/src/datasource/physical_plan/parquet/row_groups.rs#L345-L347
   
   And `PagesPruningStatistics::row_counts`
   
   
https://github.com/apache/arrow-datafusion/blob/2dad90425bacb98a3c2a4214faad53850c93104e/datafusion/core/src/datasource/physical_plan/parquet/page_filter.rs#L550-L552
   
   ### Describe alternatives you've considered
   
   I think the row counts can be found on 
https://docs.rs/parquet/latest/parquet/format/struct.ColumnMetaData.html  
   
   So this ticket should be a matter of copying the row counts correctly and 
writing some tests in 
https://github.com/apache/arrow-datafusion/blob/main/datafusion/core/tests/parquet/row_group_pruning.rs
 / 
https://github.com/apache/arrow-datafusion/blob/main/datafusion/core/tests/parquet/page_pruning.rs
   
   
   ### Additional context
   
   _No response_


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