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Dalia Sobhy 2012-11-10, 22:11
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Ted Yu 2012-11-10, 22:25
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Dalia Sobhy 2012-11-11, 16:07
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Ted Yu 2012-11-11, 16:24

Hi Ted,

I am using hbase 0.92.1

When I tried the following code I got errors:

 AggregateProtocol agg;  
  long rowcount = agg.getRowNum(ColumnInterpreter<string, int>, scan);
    
  double sum = aggregationClient.avg(TABLE_NAME, ci, scan);

even though I tried it with String (s in capital) same errors, do u know why?

> Date: Sun, 11 Nov 2012 08:24:29 -0800
> Subject: Re: Question
> From: [EMAIL PROTECTED]
> To: [EMAIL PROTECTED]
>
> Dalia:
> If you look at:
> public interface ColumnInterpreter<T, S> {
>
> you would see:
>  * @param <T> Cell value data type
>  * @param <S> Promoted data type
>
> S can represent sum of values of T. The rationale was that aggregation of
> one type (integer, e.g.) may have to be represented by another type
> (double, e.g.)
>
> From this blog you can get some history on this subject:
> http://zhihongyu.blogspot.com/2011/03/genericizing-endpointcoprocessor.html
>
> For row counting, it is already implemented:
>   public <T, S> long getRowNum(ColumnInterpreter<T, S> ci, Scan scan)
> You can embed your filter in scan object.
>
> Cheers
>
> On Sun, Nov 11, 2012 at 8:07 AM, Dalia Sobhy <[EMAIL PROTECTED]>wrote:
>
> >
> >
> > Thanks Ted :D
> >
> > But can anyone explain to me this sentence:
> >
> > ColumnInterpreter<T, S> ci
> >
> > How to set a ColumnInterpreter ?? What is T and Whats S?
> >
> > I want to perform average on an Aggregationclient, so could anyone provide
> > me with a sample code?
> >
> > Also if i want to count the number of rows which has a specific value ?
> > What to use Filters or AggregationClient?
> >
> > Thanks in advance,
> >
> > > Date: Sat, 10 Nov 2012 14:25:22 -0800
> > > Subject: Re: Question
> > > From: [EMAIL PROTECTED]
> > > To: [EMAIL PROTECTED]
> > >
> > > Take a look at AggregationClient.java and TestAggregateProtocol.java
> > >
> > > Cheers
> > >
> > > On Sat, Nov 10, 2012 at 2:11 PM, Dalia Sobhy <[EMAIL PROTECTED]
> > >wrote:
> > >
> > > >
> > > > Dear all,
> > > >
> > > > I want to use the aggregate functions, but do anyone have a code or
> > sth to
> > > > understand them ..
> > > >
> > > > Thanks
> > > >
> > > > Best Regards
> > > > Dalia
> > > >
> >
> >
     
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yuzhihong@... 2012-11-11, 20:31
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Dalia Sobhy 2012-11-13, 22:14
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Ted Yu 2012-11-13, 22:29
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Dalia Sobhy 2012-11-14, 09:09
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Dalia Sobhy 2012-11-15, 00:07
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Ted Yu 2012-11-15, 00:22