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From Graeme Wallace <graeme.wall...@farecompare.com>
Subject Re: Best way to query multiple sets of rows
Date Mon, 08 Apr 2013 18:39:35 GMT
Right - but is there a way of not tying up calling threads on the client
side - and pushing the information to the region servers so that they know
what rows to examine ?

Would this be possible in a co-processor ? (i admit i havent read up on
them yet)




On Mon, Apr 8, 2013 at 1:36 PM, Jean-Marc Spaggiari <jean-marc@spaggiari.org
> wrote:

> That's exact.
>
> In your situation, you will have to create 3 scans.
>
> One with startRow from A and endrow to B
> One with startRow from C and endrow to D
> One with startRow from E and endrow to F
>
> You can even do then in parallele if you want.
>
> JM
>
> 2013/4/8 Graeme Wallace <graeme.wallace@farecompare.com>:
> > I thought a Scan could only cope with one start row and an end row ?
> >
> >
> > On Mon, Apr 8, 2013 at 1:27 PM, Jean-Marc Spaggiari <
> jean-marc@spaggiari.org
> >> wrote:
> >
> >> Hi Greame,
> >>
> >> The scans are the right way to do that.
> >>
> >> They will give you back all the data you need, chunck by chunk. Then
> >> yoiu have to iterate over the data to do what you want with it.
> >>
> >> What was your expectation? I'm not sure I'm getting your "so that i
> >> dont have to issue sequential Scans".
> >>
> >> jM
> >>
> >> 2013/4/8 Graeme Wallace <graeme.wallace@farecompare.com>:
> >> > Hi,
> >> >
> >> > Maybe there is an obvious way but i'm not seeing it.
> >> >
> >> > I have a need to query HBase for multiple chunks of data, that is
> >> something
> >> > equivalent to
> >> >
> >> > select columns
> >> > from table
> >> > where rowid between A and B
> >> > or rowid between C and D
> >> > or rowid between E and F
> >> > etc.
> >> >
> >> > in SQL.
> >> >
> >> > Whats the best way to go about doing this so that i dont have to issue
> >> > sequential Scans ?
> >> >
> >> > --
> >> > Graeme Wallace
> >> > CTO
> >> > FareCompare.com
> >> > O: 972 588 1414
> >> > M: 214 681 9018
> >>
> >
> >
> >
> > --
> > Graeme Wallace
> > CTO
> > FareCompare.com
> > O: 972 588 1414
> > M: 214 681 9018
>



-- 
Graeme Wallace
CTO
FareCompare.com
O: 972 588 1414
M: 214 681 9018

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