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HBase, mail # user - Parallel scan in HBase


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Re: Parallel scan in HBase
Farrokh Shahriari 2013-02-01, 14:57
Tnx for your reply,
In my case, I should scan all rows( about 1 millions to 5 millions rows) in
a table & it takes a long time. I wanna know is there any way I can do it
in parallel or not ?

On Fri, Feb 1, 2013 at 5:32 PM, Mohammad Tariq <[EMAIL PROTECTED]> wrote:

> Hello Farrokh,
>
>     Scans work sequentially with one region after the other. Scans from
> client side do not go to regionservers in parallel. And, for the second
> question, the code will run at the client side.
>
> Warm Regards,
> Tariq
> https://mtariq.jux.com/
> cloudfront.blogspot.com
>
>
> On Fri, Feb 1, 2013 at 7:22 PM, Farrokh Shahriari <
> [EMAIL PROTECTED]> wrote:
>
> > 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
> >
>