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https://issues.apache.org/jira/browse/PARQUET-2254?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17706489#comment-17706489
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ASF GitHub Bot commented on PARQUET-2254:
-----------------------------------------

yabola commented on PR #1042:
URL: https://github.com/apache/parquet-mr/pull/1042#issuecomment-1488873270

   Calculate the size of nvd according to the size of bytes, I also saw similar 
logic in impala
   
https://github.com/apache/impala/blob/2c779939dc302be9ee5dd97ddf374bb043040891/be/src/kudu/util/block_bloom_filter.cc#L258-L288




> Build a BloomFilter with a more precise size
> --------------------------------------------
>
>                 Key: PARQUET-2254
>                 URL: https://issues.apache.org/jira/browse/PARQUET-2254
>             Project: Parquet
>          Issue Type: Improvement
>            Reporter: Mars
>            Assignee: Mars
>            Priority: Major
>
> h3. Why are the changes needed?
> Now the usage of bloom filter is to specify the NDV(number of distinct 
> values), and then build BloomFilter. In general scenarios, it is actually not 
> sure how much the distinct value is.
> If BloomFilter can be automatically generated according to the data, the file 
> size can be reduced and the reading efficiency can also be improved.
> h3. What changes were proposed in this pull request?
> {{DynamicBlockBloomFilter}} contains multiple {{BlockSplitBloomFilter}} as 
> candidates and inserts values in the candidates at the same time. Use the 
> largest bloom filter as an approximate deduplication counter, and then remove 
> incapable bloom filter candidates during data insertion.



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