sunchao opened a new pull request #33330:
URL: https://github.com/apache/spark/pull/33330


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   ### What changes were proposed in this pull request?
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   Fix the skipping values logic in Parquet vectorized reader when column index 
is effective, by considering nulls. Also refactored `ParquetColumnIndexSuite` 
to allow sharing more code.
   
   ### Why are the changes needed?
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   Currently, the Parquet vectorized reader may not work correctly if column 
index filtering is effective, and the data page contains null values. For 
instance, let's say we have two columns `c1: BIGINT` and `c2: STRING`, and the 
following pages:
   ```
      * c1        500       500       500       500
      *  |---------|---------|---------|---------|
      *  |-------|-----|-----|---|---|---|---|---|
      * c2     400   300   200 200 200 200 200 200
   ```
   
   and suppose we have a query like the following:
   ```sql
   SELECT * FROM t WHERE c1 = 500
   ```
   
   this will create a Parquet row range `[500, 1000)` which, when applied to 
`c2`, will require us to skip all the rows in `[400,500)`. However the current 
logic for skipping rows is via `updater.skipValues(n, valueReader)` which is 
incorrect since this skips the next `n` non-null values. In the case when nulls 
are present, this will not work correctly.
   
   ### Does this PR introduce _any_ user-facing change?
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   No
   
   ### How was this patch tested?
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   Added a new test in `ParquetColumnIndexSuite`.


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