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Re: Question
What number format did you use for the cardiac column family ?
I assume you store double as byte array.

Cheers

On Tue, Nov 13, 2012 at 2:14 PM, Dalia Sobhy <[EMAIL PROTECTED]>wrote:

> Hello Ted:
>
> I have a patient table which contains two column families: info and
> cardiac.
>
> I need to count the number of people who suffer from a particular
> diagnosis within cardiac.
>
> For instance the number of patients suffering from "heart failure"
>
> Sent from my iPad
>
> On Nov 13, 2012, at 11:00 PM, "Ted Yu" <[EMAIL PROTECTED]> wrote:
>
> > Currently http://hbase.apache.org/book.html gives me networks error.
> > You should be able to find example of how Java client connects to HBase
> cluster.
> >
> > How ColumnInterpreter is initialized depends on your schema. Can you
> tell us more about your schema ?
> >
> > Thanks
> >
> > On Tue, Nov 13, 2012 at 12:40 PM, Dalia Sobhy <
> [EMAIL PROTECTED]> wrote:
> >>
> >>
> >>
> >>
> >> Begin forwarded message:
> >>
> >>> From: Dalia Sobhy <[EMAIL PROTECTED]>
> >>> Date: November 12, 2012, 10:12:57 PM GMT+02:00
> >>> To: <[EMAIL PROTECTED]>
> >>> Subject: RE: Question
> >>>
> >>> Thanks,
> >>>
> >>> But how to initialize the ColumnInterpreter, I mean how to link it
> with a table.
> >>>
> >>> Another aspect, its my first time to use java classes for hbase, I was
> using thrift server to connect to hbase. But due to the need for aggregate
> functions i shifted to hbase 0.92.
> >>>
> >>> So could you explain to me in brief how are the java classes connected
> to hbase server.
> >>>
> >>> Thanks in advance :D
> >>>
> >>> Date: Mon, 12 Nov 2012 11:35:58 -0800
> >>>
> >>> Subject: Re: Question
> >>> From: [EMAIL PROTECTED]
> >>> To: [EMAIL PROTECTED]
> >>> CC: [EMAIL PROTECTED]
> >>>
> >>>
> >>> double is primitive type.
> >>> Replace with Double.
> >>>
> >>> Cheers
> >>>
> >>> On Mon, Nov 12, 2012 at 11:31 AM, Dalia Sobhy <
> [EMAIL PROTECTED]> wrote:
> >>>
> >>>
> >>> Syntax error on token "double", Dimensions expected after this token
> >>>
> >>> Pastebin link:
> >>> http://pastebin.com/dcvaMvLw
> >>>
> >>> I am trying to send it on the group but I dunno why hotmail disagrees
> and sends me postmaster failure so weird!!!
> >>>
> >>>
> >>> > CC: [EMAIL PROTECTED]
> >>> > From: [EMAIL PROTECTED]
> >>> > Subject: Re: Question
> >>> > Date: Sun, 11 Nov 2012 12:31:16 -0800
> >>> > To: [EMAIL PROTECTED]
> >>>
> >>> >
> >>> > What error did you get ?
> >>> > Please use pastebin to share.
> >>> >
> >>> > Thanks
> >>> >
> >>> >
> >>> >
> >>> > On Nov 11, 2012, at 11:42 AM, Dalia Sobhy <
> [EMAIL PROTECTED]> wrote:
> >>> >
> >>> > >
> >>> > > 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