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From Amit Sela <am...@infolinks.com>
Subject Re: Co-Processor in scanning the HBase's Table
Date Thu, 21 Feb 2013 17:28:26 GMT
I think that if your intention is to do some kind of scan filtering on the
server side then maybe an EndPoint coprocessor would be more fitting.
You can iterate over the InternalScanner and return a Map<> with your
filtered values.

You can also check this link:
http://hbase-coprocessor-experiments.blogspot.co.il/2011/05/extending.html

Good Luck!

On Thu, Feb 21, 2013 at 5:52 PM, Anoop John <anoop.hbase@gmail.com> wrote:

> What is this filtering at client side doing exactly?
> postScannerClose() wont deal with any scanned data.  This hook will be
> called later..  You should be using hooks with scanner's next calls.  Mind
> telling the exact thing you are doing now at client side. Then we might be
> able to suggest some thing.
>
> -Anoop-
>
> On Thu, Feb 21, 2013 at 7:14 PM, Farrokh Shahriari <
> mohandes.zebeleh.67@gmail.com> wrote:
>
> > Hello again,
> > I've used PostScannerClose Regionobserver as the hbase book (Definitive
> > Guide) says,but it doesn't seem worked.And I noticed that the
> > PostScannerClose doesn't return any value like result.
> > In fact,I just wanna doing a simple job as described below:
> > Up to now,I've used a scanner to filter the columnFamily,then on the
> client
> > side ( means at the result loop), filtered some other things,now I want
> to
> > do that after scanning each region to reduce the amount of return results
> > to client.
> >
> > Please help me,I need it asap.
> >
> > Farrokh
> >
> > On Tue, Feb 19, 2013 at 9:03 PM, Farrokh Shahriari <
> > mohandes.zebeleh.67@gmail.com> wrote:
> >
> > > Thanks you guys
> > >
> > >
> > > On Mon, Feb 18, 2013 at 12:00 PM, Amit Sela <amits@infolinks.com>
> wrote:
> > >
> > >> Yes... that was emailing half asleep... :)
> > >>
> > >> On Mon, Feb 18, 2013 at 7:23 AM, Anoop Sam John <anoopsj@huawei.com>
> > >> wrote:
> > >>
> > >> > We dont have any hook like postScan()..  In ur case you can try with
> > >> > postScannerClose()..  This will be called once per region. When the
> > >> scan on
> > >> > that region is over the scanner opened on that region will get
> closed
> > >> and
> > >> > at that time this hook will get executed.
> > >> >
> > >> > -Anoop-
> > >> > ________________________________________
> > >> > From: Farrokh Shahriari [mohandes.zebeleh.67@gmail.com]
> > >> > Sent: Monday, February 18, 2013 10:27 AM
> > >> > To: user@hbase.apache.org
> > >> > Cc: cdh-user@cloudera.org
> > >> > Subject: Re: Co-Processor in scanning the HBase's Table
> > >> >
> > >> > Thanks you Amit,I will check that.
> > >> > @Anoop: I wanna run that just after scanning a region or after
> > scanning
> > >> the
> > >> > regions that to belong to one regionserver.
> > >> >
> > >> > On Mon, Feb 18, 2013 at 7:45 AM, Anoop Sam John <anoopsj@huawei.com
> >
> > >> > wrote:
> > >> >
> > >> > > >I wanna use a custom code after scanning a large table and
prefer
> > to
> > >> run
> > >> > > the code after scanning each region
> > >> > >
> > >> > > Exactly at what point you want to run your custom code?  We have
> > >> hooks at
> > >> > > points like opening a scanner at a region, closing scanner at
a
> > >> region,
> > >> > > calling next (pre/post) etc
> > >> > >
> > >> > > -Anoop-
> > >> > > ________________________________________
> > >> > > From: Farrokh Shahriari [mohandes.zebeleh.67@gmail.com]
> > >> > > Sent: Monday, February 18, 2013 12:21 AM
> > >> > > To: cdh-user@cloudera.org; user@hbase.apache.org
> > >> > > Subject: Co-Processor in scanning the HBase's Table
> > >> > >
> > >> > > Hi there
> > >> > > I wanna use a custom code after scanning a large table and prefer
> to
> > >> run
> > >> > > the code after scanning each region.I know that I should use
> > >> > > co-processor,but don't know which of Observer,Endpoint or both
of
> > >> them I
> > >> > > should use ? Is there any simple example of them ?
> > >> > >
> > >> > > Tnx
> > >> > >
> > >> >
> > >>
> > >
> > >
> >
>

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