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HBase, mail # user - Question


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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
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Dalia Sobhy 2012-11-11, 19:42
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yuzhihong@... 2012-11-11, 20:31
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Re: Question
Dalia Sobhy 2012-11-13, 22:14
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 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
>
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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