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https://issues.apache.org/jira/browse/HBASE-11144?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14004395#comment-14004395
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ramkrishna.s.vasudevan commented on HBASE-11144:
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bq.Javadoc could be updated saying what this filter does.
Leave this. My bad i saw the comment on the constructor to be the javadoc.
> Filter to support scan multiple row key ranges
> ----------------------------------------------
>
> Key: HBASE-11144
> URL: https://issues.apache.org/jira/browse/HBASE-11144
> Project: HBase
> Issue Type: Improvement
> Components: Filters
> Reporter: Li Jiajia
> Attachments: MultiRowRangeFilter.patch, MultiRowRangeFilter2.patch,
> MultiRowRangeFilter3.patch
>
>
> HBase is quite efficient when scanning only one small row key range. If user
> needs to specify multiple row key ranges in one scan, the typical solutions
> are: 1. through FilterList which is a list of row key Filters, 2. using the
> SQL layer over HBase to join with two table, such as hive, phoenix etc.
> However, both solutions are inefficient. Both of them can’t utilize the range
> info to perform fast forwarding during scan which is quite time consuming. If
> the number of ranges are quite big (e.g. millions), join is a proper solution
> though it is slow. However, there are cases that user wants to specify a
> small number of ranges to scan (e.g. <1000 ranges). Both solutions can’t
> provide satisfactory performance in such case.
> We provide this filter (MultiRowRangeFilter) to support such use case (scan
> multiple row key ranges), which can construct the row key ranges from user
> specified sorted list and perform fast-forwarding during scan. Thus, the scan
> will be quite efficient.
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