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https://issues.apache.org/jira/browse/HBASE-15325?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15185346#comment-15185346
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Anoop Sam John commented on HBASE-15325:
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So to fix this, we can work with client side fix only?  We will see the last 
result got from RS. If it is marked partial, we will create new Scanner with 
start key as the rk of the last Result and skip the upto Cells what we got (Or 
ignore the partial Results on this row)
When batching is set, we dont know whether we have all batches for this row.  
But we can blindly think that we are at middle of this row and not all batches 
we got back.  It will fetch one full row unwantedly, when we have already 
fetched all the batches for this row and exactly at that time the region move. 
This is a very rare case.  So it is ok to do the fetch of the whole row. IMO

> ResultScanner allowing partial result will miss the rest of the row if the 
> region is moved between two rpc requests
> -------------------------------------------------------------------------------------------------------------------
>
>                 Key: HBASE-15325
>                 URL: https://issues.apache.org/jira/browse/HBASE-15325
>             Project: HBase
>          Issue Type: Bug
>          Components: dataloss, Scanners
>    Affects Versions: 1.2.0, 1.1.3
>            Reporter: Phil Yang
>            Assignee: Phil Yang
>            Priority: Critical
>         Attachments: 15325-test.txt, HBASE-15325-v1.txt, HBASE-15325-v2.txt, 
> HBASE-15325-v3.txt, HBASE-15325-v5.txt, HBASE-15325-v6.1.txt, 
> HBASE-15325-v6.2.txt, HBASE-15325-v6.3.txt, HBASE-15325-v6.4.txt, 
> HBASE-15325-v6.5.txt, HBASE-15325-v6.txt
>
>
> HBASE-11544 allow scan rpc return partial of a row to reduce memory usage for 
> one rpc request. And client can setAllowPartial or setBatch to get several 
> cells in a row instead of the whole row.
> However, the status of the scanner is saved on server and we need this to get 
> the next part if there is a partial result before. If we move the region to 
> another RS, client will get a NotServingRegionException and open a new 
> scanner to the new RS which will be regarded as a new scan from the end of 
> this row. So the rest cells of the row of last result will be missing.



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