Miroslav Holubec created DRILL-4601:
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             Summary: Partitioning based on the parquet statistics
                 Key: DRILL-4601
                 URL: https://issues.apache.org/jira/browse/DRILL-4601
             Project: Apache Drill
          Issue Type: Improvement
          Components: Query Planning & Optimization
            Reporter: Miroslav Holubec


It can really help performance to extend current partitioning idea implemented 
in DRILL-3333 even further.
Currently partitioning is based on statistics, when min value equals to max 
value for whole file. Based on this files are removed from scan in planning 
phase. Problem with this is, that it leads to many small parquet files, which 
is not fine in HDFS world. Also only few columns are partitioned.

I would like to extend this idea to use all statistics for all columns. So if 
value should equal to constant, remove all files from plan which have 
statistics off. This will really help performance for scans over many parquet 
files.

I have initial patch ready, currently just to give an idea.



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