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: [email protected] [[email protected]]
Sent: Wednesday, October 10, 2012 7:51 PM
To: [email protected]
Cc: [email protected]; [email protected]
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 <[email protected]> wrote: -----
To: "[email protected]" <[email protected]>,
"[email protected]" <[email protected]>
From: Anoop Sam John <[email protected]>
Date: 10/10/2012 06:18PM
Subject: RE: HBase table - distinct values
Hi
Your schema? 'deptno' is a cf:qualifier?
-Anoop-
________________________________________
From: [email protected] [[email protected]]
Sent: Wednesday, October 10, 2012 4:29 PM
To: [email protected]; [email protected]
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
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