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https://issues.apache.org/jira/browse/HIVE-9188?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Prasanth Jayachandran updated HIVE-9188:
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Attachment: HIVE-9188.5.patch
[~owen.omalley] Updated patch creates separate streams for bloom filter. It
only has row group level bloom filter are dropped. The disk IO is merged while
reading row index.
[~gopalv] Addressed all your review comments. Additionally FileDump will
aggregate the bloom filters to stripe level and will print the stats. You might
want to use
{code}
hive --orcfiledump --rowindex=<column_index_csv_list> <file_path>
{code}
> BloomFilter in ORC row group index
> ----------------------------------
>
> Key: HIVE-9188
> URL: https://issues.apache.org/jira/browse/HIVE-9188
> Project: Hive
> Issue Type: New Feature
> Components: File Formats
> Affects Versions: 0.15.0
> Reporter: Prasanth Jayachandran
> Assignee: Prasanth Jayachandran
> Labels: orcfile
> Attachments: HIVE-9188.1.patch, HIVE-9188.2.patch, HIVE-9188.3.patch,
> HIVE-9188.4.patch, HIVE-9188.5.patch
>
>
> BloomFilters are well known probabilistic data structure for set membership
> checking. We can use bloom filters in ORC index for better row group pruning.
> Currently, ORC row group index uses min/max statistics to eliminate row
> groups (stripes as well) that do not satisfy predicate condition specified in
> the query. But in some cases, the efficiency of min/max based elimination is
> not optimal (unsorted columns with wide range of entries). Bloom filters can
> be an effective and efficient alternative for row group/split elimination for
> point queries or queries with IN clause.
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