jychen7 commented on issue #4028:
URL: 
https://github.com/apache/arrow-datafusion/issues/4028#issuecomment-1501321250

   I think it is a good idea. I confirm it would help improve performance by 
30x in 
https://github.com/apache/arrow-datafusion/issues/5404#issuecomment-1501221831.
   
   ---
   
   I am thinking to pick this up but seems the work is not as trivial as I 
thought. Following are my two cents' thoughts.
   
   Related code to improve is following
   
https://github.com/apache/arrow-datafusion/blob/7545177001b9dc04951f0c1c2008509f3895de8e/datafusion/core/src/datasource/listing/table.rs#L736-L756
   
   > 1. The FileFormat is parquet
   
   This is trivial, we can `match self.options.format` with `ParquetFormat`
   
   > 2. Parquet predicate pushdown is enabled
   
   This setting could come from `ParquetExec.pushdown_filters` or 
`ConfigOptions` (more specifically, 
`ConfigOptions.execution.parquet.pushdown_filters`)
   
   
https://github.com/apache/arrow-datafusion/blob/7545177001b9dc04951f0c1c2008509f3895de8e/datafusion/core/src/physical_plan/file_format/parquet.rs#L393
   
   However, when `ListingTable.supports_filter_pushdown` is called, 
`ParquetExec` is not created yet, nor does `SessionState` being passed as input.
   
   Idea: shall we add `state: &SessionState` as input for 
`ListingTable.supports_filter_pushdown`, the same as `ListingTable.scan` ❓ 
   
   
https://github.com/apache/arrow-datafusion/blob/7545177001b9dc04951f0c1c2008509f3895de8e/datafusion/core/src/datasource/listing/table.rs#L668-L670
   
   > 3. The predicate is fully pushed down by ParquetExec (not all predicates 
are supported)
   
   is it making sure the `row_filter` is built from the `predicate` without 
error? If so, seems it requires converting a logical `Expr` to `PhysicalExpr` 
first.
   
   
https://github.com/apache/arrow-datafusion/blob/7545177001b9dc04951f0c1c2008509f3895de8e/datafusion/core/src/physical_plan/file_format/parquet.rs#L527-L547
   


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