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Posted to user@hbase.apache.org by ra...@polarisFT.com on 2012/10/10 12:59:03 UTC
HBase table - distinct values
Hi all,
Is it possible to select distinct value from Hbase table.
Example :-
what is the equivalant code for the below Oracle code in Hbase ?
Select count (distinct deptno) from emp ;
Regards
Raviprasad. T
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Visit us at http://www.polarisFT.com
RE: HBase table - distinct values
Posted by Nitin Pawar <ni...@gmail.com>.
You may try define a hive table with hbase storage handler n then query it
..though response time will be slow based on how much data you have
On Oct 11, 2012 4:19 PM, <ra...@polarisft.com> wrote:
> Hi Anoop,
> Thanks a lot for your reply,
> Actually our requirment is just to count the distinct deptno from emp
> ( Hbase table), We are running various pentaho jobs and we need to test
> the validity of the results, for that we need the below query.
>
> We need a query to select distinct deptno from emp Hbase table.
>
> Example :-
> HBase Table name :- emp, column_family := cf
> Let us say deptno is the field in the column family cf
>
> emp
> ----
> deptno
> 10
> 20
> 30
> 10
> 10
> 10
>
> The Result should be
> The count (distinct deptno) = 3
>
> We need just the query to know the count of distinct deptno .
>
> Thanks
> Regards
> Raviprasad. T
> Mobile :- 91- 9894769541
>
>
> -----Anoop Sam John <an...@huawei.com> wrote: -----
> To: "user@hbase.apache.org" <us...@hbase.apache.org>
> From: Anoop Sam John <an...@huawei.com>
> Date: 10/11/2012 09:33AM
> Cc: "hbase-user@hadoop.apache.org" <hb...@hadoop.apache.org>
> Subject: RE: HBase table - distinct values
>
> Hi Ravi
> If dept_no is a CF:qualifier, to know all the dept numbers
> (distinct or not) you need a full table scan. As Doug said if it is a
> frequent online query don't think MR is a good choice.. If the data in
> your emp table is huge a full table scan also wont be that good I feel....
> Can you guys think about storing dept number in another table? If you
> people need query like select <empdetails> from emp where dept_no=? (this
> query also) you can think about creating secondary index implementation
> and indexing dept_no... You can use index table for above query as well as
> the 1st one you asked about. :)
>
> -Anoop-
> ________________________________________
> From: raviprasad.t@polarisFT.com [raviprasad.t@polarisFT.com]
> Sent: Wednesday, October 10, 2012 7:51 PM
> To: user@hbase.apache.org
> Cc: hbase-user@hadoop.apache.org; user@hbase.apache.org
> Subject: RE: HBase table - distinct values
>
> Hi,
> Hbase table name :- emp
> Column family :- cf
> Under the column family cf we will be having the field name deptno
>
>
> Regards
> Raviprasad. T
> Mobile :- 91- 9894769541
>
>
> -----Anoop Sam John <an...@huawei.com> wrote: -----
> To: "user@hbase.apache.org" <us...@hbase.apache.org>, "
> hbase-user@hadoop.apache.org" <hb...@hadoop.apache.org>
> From: Anoop Sam John <an...@huawei.com>
> Date: 10/10/2012 06:18PM
> Subject: RE: HBase table - distinct values
>
> Hi
> Your schema? 'deptno' is a cf:qualifier?
>
> -Anoop-
> ________________________________________
> From: raviprasad.t@polarisFT.com [raviprasad.t@polarisFT.com]
> Sent: Wednesday, October 10, 2012 4:29 PM
> To: user@hbase.apache.org; hbase-user@hadoop.apache.org
> Subject: HBase table - distinct values
>
> Hi all,
> Is it possible to select distinct value from Hbase table.
>
> Example :-
> what is the equivalant code for the below Oracle code in Hbase ?
>
> Select count (distinct deptno) from emp ;
>
> Regards
> Raviprasad. T
>
>
> This e-Mail may contain proprietary and confidential information and is
> sent for the intended recipient(s) only. If by an addressing or
> transmission error this mail has been misdirected to you, you are requested
> to delete this mail immediately. You are also hereby notified that any use,
> any form of reproduction, dissemination, copying, disclosure, modification,
> distribution and/or publication of this e-mail message, contents or its
> attachment other than by its intended recipient/s is strictly prohibited.
>
> Visit us at http://www.polarisFT.com
>
>
> This e-Mail may contain proprietary and confidential information and is
> sent for the intended recipient(s) only. If by an addressing or
> transmission error this mail has been misdirected to you, you are requested
> to delete this mail immediately. You are also hereby notified that any use,
> any form of reproduction, dissemination, copying, disclosure, modification,
> distribution and/or publication of this e-mail message, contents or its
> attachment other than by its intended recipient/s is strictly prohibited.
>
> Visit us at http://www.polarisFT.com
>
>
> This e-Mail may contain proprietary and confidential information and is
> sent for the intended recipient(s) only. If by an addressing or
> transmission error this mail has been misdirected to you, you are requested
> to delete this mail immediately. You are also hereby notified that any use,
> any form of reproduction, dissemination, copying, disclosure, modification,
> distribution and/or publication of this e-mail message, contents or its
> attachment other than by its intended recipient/s is strictly prohibited.
>
> Visit us at http://www.polarisFT.com
>
RE: HBase table - distinct values
Posted by ra...@polarisFT.com.
Hi Anoop,
Thanks a lot for your reply,
Actually our requirment is just to count the distinct deptno from emp ( Hbase table), We are running various pentaho jobs and we need to test the validity of the results, for that we need the below query.
We need a query to select distinct deptno from emp Hbase table.
Example :-
HBase Table name :- emp, column_family := cf
Let us say deptno is the field in the column family cf
emp
----
deptno
10
20
30
10
10
10
The Result should be
The count (distinct deptno) = 3
We need just the query to know the count of distinct deptno .
Thanks
Regards
Raviprasad. T
Mobile :- 91- 9894769541
-----Anoop Sam John <an...@huawei.com> wrote: -----
To: "user@hbase.apache.org" <us...@hbase.apache.org>
From: Anoop Sam John <an...@huawei.com>
Date: 10/11/2012 09:33AM
Cc: "hbase-user@hadoop.apache.org" <hb...@hadoop.apache.org>
Subject: RE: HBase table - distinct values
Hi Ravi
If dept_no is a CF:qualifier, to know all the dept numbers (distinct or not) you need a full table scan. As Doug said if it is a frequent online query don't think MR is a good choice.. If the data in your emp table is huge a full table scan also wont be that good I feel.... Can you guys think about storing dept number in another table? If you people need query like select <empdetails> from emp where dept_no=? (this query also) you can think about creating secondary index implementation and indexing dept_no... You can use index table for above query as well as the 1st one you asked about. :)
-Anoop-
________________________________________
From: raviprasad.t@polarisFT.com [raviprasad.t@polarisFT.com]
Sent: Wednesday, October 10, 2012 7:51 PM
To: user@hbase.apache.org
Cc: hbase-user@hadoop.apache.org; user@hbase.apache.org
Subject: RE: HBase table - distinct values
Hi,
Hbase table name :- emp
Column family :- cf
Under the column family cf we will be having the field name deptno
Regards
Raviprasad. T
Mobile :- 91- 9894769541
-----Anoop Sam John <an...@huawei.com> wrote: -----
To: "user@hbase.apache.org" <us...@hbase.apache.org>, "hbase-user@hadoop.apache.org" <hb...@hadoop.apache.org>
From: Anoop Sam John <an...@huawei.com>
Date: 10/10/2012 06:18PM
Subject: RE: HBase table - distinct values
Hi
Your schema? 'deptno' is a cf:qualifier?
-Anoop-
________________________________________
From: raviprasad.t@polarisFT.com [raviprasad.t@polarisFT.com]
Sent: Wednesday, October 10, 2012 4:29 PM
To: user@hbase.apache.org; hbase-user@hadoop.apache.org
Subject: HBase table - distinct values
Hi all,
Is it possible to select distinct value from Hbase table.
Example :-
what is the equivalant code for the below Oracle code in Hbase ?
Select count (distinct deptno) from emp ;
Regards
Raviprasad. T
This e-Mail may contain proprietary and confidential information and is sent for the intended recipient(s) only. If by an addressing or transmission error this mail has been misdirected to you, you are requested to delete this mail immediately. You are also hereby notified that any use, any form of reproduction, dissemination, copying, disclosure, modification, distribution and/or publication of this e-mail message, contents or its attachment other than by its intended recipient/s is strictly prohibited.
Visit us at http://www.polarisFT.com
This e-Mail may contain proprietary and confidential information and is sent for the intended recipient(s) only. If by an addressing or transmission error this mail has been misdirected to you, you are requested to delete this mail immediately. You are also hereby notified that any use, any form of reproduction, dissemination, copying, disclosure, modification, distribution and/or publication of this e-mail message, contents or its attachment other than by its intended recipient/s is strictly prohibited.
Visit us at http://www.polarisFT.com
This e-Mail may contain proprietary and confidential information and is sent for the intended recipient(s) only. If by an addressing or transmission error this mail has been misdirected to you, you are requested to delete this mail immediately. You are also hereby notified that any use, any form of reproduction, dissemination, copying, disclosure, modification, distribution and/or publication of this e-mail message, contents or its attachment other than by its intended recipient/s is strictly prohibited.
Visit us at http://www.polarisFT.com
RE: HBase table - distinct values
Posted by "Ramkrishna.S.Vasudevan" <ra...@huawei.com>.
Are you planning to use region splits? Can the rowkey have the deptno?
Having dept no in another table, may be having a reverse mapping of deptno
to empno may be helpful too if such queries are frequent.
Regards
Ram
> -----Original Message-----
> From: Anoop Sam John [mailto:anoopsj@huawei.com]
> Sent: Thursday, October 11, 2012 9:32 AM
> To: user@hbase.apache.org
> Cc: hbase-user@hadoop.apache.org
> Subject: RE: HBase table - distinct values
>
> Hi Ravi
> If dept_no is a CF:qualifier, to know all the dept numbers
> (distinct or not) you need a full table scan. As Doug said if it is a
> frequent online query don't think MR is a good choice.. If the data in
> your emp table is huge a full table scan also wont be that good I
> feel.... Can you guys think about storing dept number in another
> table? If you people need query like select <empdetails> from emp
> where dept_no=? (this query also) you can think about creating
> secondary index implementation and indexing dept_no... You can use
> index table for above query as well as the 1st one you asked about. :)
>
> -Anoop-
> ________________________________________
> From: raviprasad.t@polarisFT.com [raviprasad.t@polarisFT.com]
> Sent: Wednesday, October 10, 2012 7:51 PM
> To: user@hbase.apache.org
> Cc: hbase-user@hadoop.apache.org; user@hbase.apache.org
> Subject: RE: HBase table - distinct values
>
> Hi,
> Hbase table name :- emp
> Column family :- cf
> Under the column family cf we will be having the field name
> deptno
>
>
> Regards
> Raviprasad. T
> Mobile :- 91- 9894769541
>
>
> -----Anoop Sam John <an...@huawei.com> wrote: -----
> To: "user@hbase.apache.org" <us...@hbase.apache.org>, "hbase-
> user@hadoop.apache.org" <hb...@hadoop.apache.org>
> From: Anoop Sam John <an...@huawei.com>
> Date: 10/10/2012 06:18PM
> Subject: RE: HBase table - distinct values
>
> Hi
> Your schema? 'deptno' is a cf:qualifier?
>
> -Anoop-
> ________________________________________
> From: raviprasad.t@polarisFT.com [raviprasad.t@polarisFT.com]
> Sent: Wednesday, October 10, 2012 4:29 PM
> To: user@hbase.apache.org; hbase-user@hadoop.apache.org
> Subject: HBase table - distinct values
>
> Hi all,
> Is it possible to select distinct value from Hbase table.
>
> Example :-
> what is the equivalant code for the below Oracle code in Hbase ?
>
> Select count (distinct deptno) from emp ;
>
> Regards
> Raviprasad. T
>
>
> This e-Mail may contain proprietary and confidential information and is
> sent for the intended recipient(s) only. If by an addressing or
> transmission error this mail has been misdirected to you, you are
> requested to delete this mail immediately. You are also hereby notified
> that any use, any form of reproduction, dissemination, copying,
> disclosure, modification, distribution and/or publication of this e-
> mail message, contents or its attachment other than by its intended
> recipient/s is strictly prohibited.
>
> Visit us at http://www.polarisFT.com
>
>
> This e-Mail may contain proprietary and confidential information and is
> sent for the intended recipient(s) only. If by an addressing or
> transmission error this mail has been misdirected to you, you are
> requested to delete this mail immediately. You are also hereby notified
> that any use, any form of reproduction, dissemination, copying,
> disclosure, modification, distribution and/or publication of this e-
> mail message, contents or its attachment other than by its intended
> recipient/s is strictly prohibited.
>
> Visit us at http://www.polarisFT.com=
Re: HBase table - distinct values
Posted by yutoo yanio <yu...@gmail.com>.
you can create a table with key=deptno or every value that you need
distinct value of it.
scan of this table shows the distinct values.
On Thu, Oct 11, 2012 at 8:22 AM, Ramkrishna.S.Vasudevan <
ramkrishna.vasudevan@huawei.com> wrote:
> Are you planning to use region splits? Can the rowkey have the deptno?
>
> Having dept no in another table, may be having a reverse mapping of deptno
> to empno may be helpful too if such queries are frequent.
>
> Regards
> Ram
> > -----Original Message-----
> > From: Anoop Sam John [mailto:anoopsj@huawei.com]
> > Sent: Thursday, October 11, 2012 9:32 AM
> > To: user@hbase.apache.org
> > Cc: hbase-user@hadoop.apache.org
> > Subject: RE: HBase table - distinct values
> >
> > Hi Ravi
> > If dept_no is a CF:qualifier, to know all the dept numbers
> > (distinct or not) you need a full table scan. As Doug said if it is a
> > frequent online query don't think MR is a good choice.. If the data in
> > your emp table is huge a full table scan also wont be that good I
> > feel.... Can you guys think about storing dept number in another
> > table? If you people need query like select <empdetails> from emp
> > where dept_no=? (this query also) you can think about creating
> > secondary index implementation and indexing dept_no... You can use
> > index table for above query as well as the 1st one you asked about. :)
> >
> > -Anoop-
> > ________________________________________
> > From: raviprasad.t@polarisFT.com [raviprasad.t@polarisFT.com]
> > Sent: Wednesday, October 10, 2012 7:51 PM
> > To: user@hbase.apache.org
> > Cc: hbase-user@hadoop.apache.org; user@hbase.apache.org
> > Subject: RE: HBase table - distinct values
> >
> > Hi,
> > Hbase table name :- emp
> > Column family :- cf
> > Under the column family cf we will be having the field name
> > deptno
> >
> >
> > Regards
> > Raviprasad. T
> > Mobile :- 91- 9894769541
> >
> >
> > -----Anoop Sam John <an...@huawei.com> wrote: -----
> > To: "user@hbase.apache.org" <us...@hbase.apache.org>, "hbase-
> > user@hadoop.apache.org" <hb...@hadoop.apache.org>
> > From: Anoop Sam John <an...@huawei.com>
> > Date: 10/10/2012 06:18PM
> > Subject: RE: HBase table - distinct values
> >
> > Hi
> > Your schema? 'deptno' is a cf:qualifier?
> >
> > -Anoop-
> > ________________________________________
> > From: raviprasad.t@polarisFT.com [raviprasad.t@polarisFT.com]
> > Sent: Wednesday, October 10, 2012 4:29 PM
> > To: user@hbase.apache.org; hbase-user@hadoop.apache.org
> > Subject: HBase table - distinct values
> >
> > Hi all,
> > Is it possible to select distinct value from Hbase table.
> >
> > Example :-
> > what is the equivalant code for the below Oracle code in Hbase ?
> >
> > Select count (distinct deptno) from emp ;
> >
> > Regards
> > Raviprasad. T
> >
> >
> > This e-Mail may contain proprietary and confidential information and is
> > sent for the intended recipient(s) only. If by an addressing or
> > transmission error this mail has been misdirected to you, you are
> > requested to delete this mail immediately. You are also hereby notified
> > that any use, any form of reproduction, dissemination, copying,
> > disclosure, modification, distribution and/or publication of this e-
> > mail message, contents or its attachment other than by its intended
> > recipient/s is strictly prohibited.
> >
> > Visit us at http://www.polarisFT.com
> >
> >
> > This e-Mail may contain proprietary and confidential information and is
> > sent for the intended recipient(s) only. If by an addressing or
> > transmission error this mail has been misdirected to you, you are
> > requested to delete this mail immediately. You are also hereby notified
> > that any use, any form of reproduction, dissemination, copying,
> > disclosure, modification, distribution and/or publication of this e-
> > mail message, contents or its attachment other than by its intended
> > recipient/s is strictly prohibited.
> >
> > Visit us at http://www.polarisFT.com=
>
>
RE: HBase table - distinct values
Posted by Anoop Sam John <an...@huawei.com>.
Hi Ravi
If dept_no is a CF:qualifier, to know all the dept numbers (distinct or not) you need a full table scan. As Doug said if it is a frequent online query don't think MR is a good choice.. If the data in your emp table is huge a full table scan also wont be that good I feel.... Can you guys think about storing dept number in another table? If you people need query like select <empdetails> from emp where dept_no=? (this query also) you can think about creating secondary index implementation and indexing dept_no... You can use index table for above query as well as the 1st one you asked about. :)
-Anoop-
________________________________________
From: raviprasad.t@polarisFT.com [raviprasad.t@polarisFT.com]
Sent: Wednesday, October 10, 2012 7:51 PM
To: user@hbase.apache.org
Cc: hbase-user@hadoop.apache.org; user@hbase.apache.org
Subject: RE: HBase table - distinct values
Hi,
Hbase table name :- emp
Column family :- cf
Under the column family cf we will be having the field name deptno
Regards
Raviprasad. T
Mobile :- 91- 9894769541
-----Anoop Sam John <an...@huawei.com> wrote: -----
To: "user@hbase.apache.org" <us...@hbase.apache.org>, "hbase-user@hadoop.apache.org" <hb...@hadoop.apache.org>
From: Anoop Sam John <an...@huawei.com>
Date: 10/10/2012 06:18PM
Subject: RE: HBase table - distinct values
Hi
Your schema? 'deptno' is a cf:qualifier?
-Anoop-
________________________________________
From: raviprasad.t@polarisFT.com [raviprasad.t@polarisFT.com]
Sent: Wednesday, October 10, 2012 4:29 PM
To: user@hbase.apache.org; hbase-user@hadoop.apache.org
Subject: HBase table - distinct values
Hi all,
Is it possible to select distinct value from Hbase table.
Example :-
what is the equivalant code for the below Oracle code in Hbase ?
Select count (distinct deptno) from emp ;
Regards
Raviprasad. T
This e-Mail may contain proprietary and confidential information and is sent for the intended recipient(s) only. If by an addressing or transmission error this mail has been misdirected to you, you are requested to delete this mail immediately. You are also hereby notified that any use, any form of reproduction, dissemination, copying, disclosure, modification, distribution and/or publication of this e-mail message, contents or its attachment other than by its intended recipient/s is strictly prohibited.
Visit us at http://www.polarisFT.com
This e-Mail may contain proprietary and confidential information and is sent for the intended recipient(s) only. If by an addressing or transmission error this mail has been misdirected to you, you are requested to delete this mail immediately. You are also hereby notified that any use, any form of reproduction, dissemination, copying, disclosure, modification, distribution and/or publication of this e-mail message, contents or its attachment other than by its intended recipient/s is strictly prohibited.
Visit us at http://www.polarisFT.com
RE: HBase table - distinct values
Posted by ra...@polarisFT.com.
Hi,
Hbase table name :- emp
Column family :- cf
Under the column family cf we will be having the field name deptno
Regards
Raviprasad. T
Mobile :- 91- 9894769541
-----Anoop Sam John <an...@huawei.com> wrote: -----
To: "user@hbase.apache.org" <us...@hbase.apache.org>, "hbase-user@hadoop.apache.org" <hb...@hadoop.apache.org>
From: Anoop Sam John <an...@huawei.com>
Date: 10/10/2012 06:18PM
Subject: RE: HBase table - distinct values
Hi
Your schema? 'deptno' is a cf:qualifier?
-Anoop-
________________________________________
From: raviprasad.t@polarisFT.com [raviprasad.t@polarisFT.com]
Sent: Wednesday, October 10, 2012 4:29 PM
To: user@hbase.apache.org; hbase-user@hadoop.apache.org
Subject: HBase table - distinct values
Hi all,
Is it possible to select distinct value from Hbase table.
Example :-
what is the equivalant code for the below Oracle code in Hbase ?
Select count (distinct deptno) from emp ;
Regards
Raviprasad. T
This e-Mail may contain proprietary and confidential information and is sent for the intended recipient(s) only. If by an addressing or transmission error this mail has been misdirected to you, you are requested to delete this mail immediately. You are also hereby notified that any use, any form of reproduction, dissemination, copying, disclosure, modification, distribution and/or publication of this e-mail message, contents or its attachment other than by its intended recipient/s is strictly prohibited.
Visit us at http://www.polarisFT.com
This e-Mail may contain proprietary and confidential information and is sent for the intended recipient(s) only. If by an addressing or transmission error this mail has been misdirected to you, you are requested to delete this mail immediately. You are also hereby notified that any use, any form of reproduction, dissemination, copying, disclosure, modification, distribution and/or publication of this e-mail message, contents or its attachment other than by its intended recipient/s is strictly prohibited.
Visit us at http://www.polarisFT.com
RE: HBase table - distinct values
Posted by Anoop Sam John <an...@huawei.com>.
Hi
Your schema? 'deptno' is a cf:qualifier?
-Anoop-
________________________________________
From: raviprasad.t@polarisFT.com [raviprasad.t@polarisFT.com]
Sent: Wednesday, October 10, 2012 4:29 PM
To: user@hbase.apache.org; hbase-user@hadoop.apache.org
Subject: HBase table - distinct values
Hi all,
Is it possible to select distinct value from Hbase table.
Example :-
what is the equivalant code for the below Oracle code in Hbase ?
Select count (distinct deptno) from emp ;
Regards
Raviprasad. T
This e-Mail may contain proprietary and confidential information and is sent for the intended recipient(s) only. If by an addressing or transmission error this mail has been misdirected to you, you are requested to delete this mail immediately. You are also hereby notified that any use, any form of reproduction, dissemination, copying, disclosure, modification, distribution and/or publication of this e-mail message, contents or its attachment other than by its intended recipient/s is strictly prohibited.
Visit us at http://www.polarisFT.com
Re: HBase table - distinct values
Posted by Jean-Marc Spaggiari <je...@spaggiari.org>.
Hi Raviprasad,
What you can do, if deptno is you key, or the first part of you key,
is to scan for the first entry, then increment it by one and scan with
this value.
Let's take an example.
Key format is DEPTNO + ID (XXYY)
You table content is:
0101
0102
0106
0207
0212
0243
0419
0441
If you scan for the first entry you will find 0101. You extract 01
form that. Then you search for the next DEPTID just above this one.
You first key for the search will be 02. And you will find 0207. You
do the same. Start key for your search will be 03 and you will find
04.
And so on.
the main issue you will have is that is you have only few DEPTNO, you
will hotspot one server, then another one, and so on. So may you
should think about your schema first. Like you can have a table with
only the deptno so to get the list of distincts deptno you just scan
this table? etc.
JM
2012/10/10, raviprasad.t@polarisft.com <ra...@polarisft.com>:
> Hi all,
> Is it possible to select distinct value from Hbase table.
>
> Example :-
> what is the equivalant code for the below Oracle code in Hbase ?
>
> Select count (distinct deptno) from emp ;
>
> Regards
> Raviprasad. T
>
>
> This e-Mail may contain proprietary and confidential information and is sent
> for the intended recipient(s) only. If by an addressing or transmission
> error this mail has been misdirected to you, you are requested to delete
> this mail immediately. You are also hereby notified that any use, any form
> of reproduction, dissemination, copying, disclosure, modification,
> distribution and/or publication of this e-mail message, contents or its
> attachment other than by its intended recipient/s is strictly prohibited.
>
> Visit us at http://www.polarisFT.com
>
Re: HBase table - distinct values
Posted by Doug Meil <do...@explorysmedical.com>.
Typically this is something done as a MapReduce job.
http://hbase.apache.org/book.html#mapreduce.example
7.2.4. HBase MapReduce Summary to HBase Example
However, if this is an operation to be performed frequently by an
application then doing frequent MapReduce jobs for summaries probably
isn't the best idea. Either produce periodic summaries into another Hbase
table, or denormalize and keep track of the required summaries upon data
load.
On 10/10/12 6:59 AM, "raviprasad.t@polarisFT.com"
<ra...@polarisFT.com> wrote:
>Hi all,
> Is it possible to select distinct value from Hbase table.
>
>Example :-
> what is the equivalant code for the below Oracle code in Hbase ?
>
> Select count (distinct deptno) from emp ;
>
>Regards
>Raviprasad. T
>
>
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