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HBase, mail # user - Parallel scan in HBase


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Re: Parallel scan in HBase
lars hofhansl 2013-02-01, 15:46
The scan contract in HBase is that all rows are returned in order, so all regions have to be traversed in order as well.
It would be nice to add some facility to HBase to performs the scanning in parallel.

________________________________
 From: Farrokh Shahriari <[EMAIL PROTECTED]>
To: [EMAIL PROTECTED]
Sent: Friday, February 1, 2013 5:52 AM
Subject: Parallel scan in HBase
 
Hi there
I have two question about scan in Hbase :
1) Does scan operation with specific filter run in parallel on different
regionservers ?
2) I wanna know whether this code runs at client side for searching the
retrieved results or not ?

         for (Result result : scanner1) {
                         for (KeyValue kv : result.raw()) {
                         //
                         // some coeds
                         //
                     }
               }
Farrokh Shahriari