Gabriel39 opened a new pull request, #67573:
URL: https://github.com/apache/doris/pull/67573

   ### What problem does this PR solve?
   
   Issue Number: None
   
   Related PR: None
   
   Legacy parquet-mr and parquet-cpp writers can under-report Parquet null 
counts. Format v2 treated a reported zero as proof that a row group or page had 
no NULL values, so `IS NULL` pruning could drop matching rows.
   
   ### What is changed?
   
   - Derive null-count trust from Parquet `created_by` in format v2.
   - Conservatively retain NULL candidates for affected legacy writer versions 
at row-group and page-index pruning layers.
   - Preserve min/max pruning and existing behavior for fixed or unknown 
writers.
   
   ### Release note
   
   Avoid incorrect `IS NULL` pruning for Parquet files produced by affected 
legacy writers.
   
   ### Check List (For Author)
   
   - Test: Unit Test
       - `NativeParquetStatisticsTest.*` (19 tests passed with ASAN)
   - Behavior changed: Yes. Format v2 no longer trusts null counts from 
affected legacy Parquet writers for metadata pruning.
   - Does this need documentation: No
   


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