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https://issues.apache.org/jira/browse/HBASE-5489?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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David S. Wang reopened HBASE-5489:
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The comment for getRegionsInRange() has an error.  Submitting patch to fix that.
                
> Add HTable accessor to get regions for a key range
> --------------------------------------------------
>
>                 Key: HBASE-5489
>                 URL: https://issues.apache.org/jira/browse/HBASE-5489
>             Project: HBase
>          Issue Type: Improvement
>          Components: client
>            Reporter: David S. Wang
>            Assignee: David S. Wang
>            Priority: Minor
>             Fix For: 0.92.1, 0.94.0
>
>         Attachments: HBASE-5489-2.patch, HBASE-5489-3-0.92.1.patch, 
> HBASE-5489-3.patch, HBASE-5489-4.patch
>
>
> It would be nice to have an accessor to find all regions that overlap with a 
> particular range of keys. Right now, the only way to accomplish that is to 
> call HTable.getStartEndKeys(), then follow that with calls to 
> getRegionLocation() for the range of keys you are interested in.  This 
> algorithm has 2 drawbacks:
> * It returns more keys than is necessary most of the time.  This is 
> especially evident if there are a lot of regions comprising the table and the 
> range of keys is small.
> * It always does a scan of .META. via MetaScannerVisitor for at least 
> HTable.getStartEndKeys(), and perhaps for HRegionLocations that are not 
> already cached by the client.
> An accessor that limited its scans to a specified range could avoid scanning 
> .META. at all if the HRegionLocations being fetched were already cached by 
> the client, thereby potentially making this operation faster in common cases.
> Here's a proposal for the accessor:
>   /**
>    * Get the corresponding regions for an arbitrary range of keys.
>    * <p>
>    * @param startRow Starting row in range, inclusive
>    * @param endRow Ending row in range, inclusive
>    * @return A list of HRegionLocations corresponding to the regions that
>    * contain the specified range
>    * @throws IOException if a remote or network exception occurs
>    */
>   public List<HRegionLocation> getRegionsInRange(final byte [] startKey,
>     final byte [] endKey) throws IOException

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