andrei-ionescu commented on issue #1383:
URL: 
https://github.com/apache/arrow-datafusion/issues/1383#issuecomment-984597063


   I've been looking at the source code and it seems that the statistics are 
taken into account only for the top level columns. In the majority of places I 
see `schema.fields()` were `schema` is Arrow schema and `fields()` returns only 
top level fields.
   
   Parquet, on the other side have statistics for all columns, regardless of 
the nested level.
   
   I do understand the "quick and dirty workaround" and in regards to it I have 
the following questions:
   - Is datafusion query engine using the column stats?
   - What about writing parquet files? Shouldn't those file be written with 
stats for all columns?
   


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