In HBase the concept of "column qualifiers" is interesting, it can be
created on fly for a "column-family" So it is as good as tagging the data.
Hence, you can get all rows belonging to particular tag/qualifier using
rowscan. I'm not sure if this answers your query.

I know they are always sorted but if they are how do you know which row key
> belong to which data? Currently I use a row key of ID|Date
>



-Thanks,
Dani Rayan.
http://www.cc.gatech.edu/~iar3/ <http://www.cc.gatech.edu/%7Eiar3/>

P.S.  I missed "column-family"  in previous email

On Sat, Jan 29, 2011 at 1:07 AM, Dani Rayan <[email protected]> wrote:

> Hey can explain your query with example ?
>
>
> I know they are always sorted but if they are how do you know which row key
>> belong to which data? Currently I use a row key of ID|Date
>>
>
> > I don't clearly understand "which data", there are few things like
> getFamilyMap etc. which allows you to get more info about the table.
>
> In HBase the concept of "column qualifiers" is interesting, it can be
> created on fly for a "column-qualifier" So it is as good as tagging the
> data. Hence, you can get all rows belonging to particular tag/qualifier
> using rowscan. I'm not sure if this answers your query.
>
> -Thanks,
> Dani Rayan.
> http://www.cc.gatech.edu/~iar3/ <http://www.cc.gatech.edu/%7Eiar3/>
>
> On Fri, Jan 28, 2011 at 3:45 PM, Peter Haidinyak <[email protected]>wrote:
>
>> I know they are always sorted but if they are how do you know which row
>> key belong to which data? Currently I use a row key of ID|Date so I always
>> know what the startrow and endrow should be. I know I'm missing something
>> really fundamental here. :-(
>>
>> Thanks
>>
>> -Pete
>>
>> -----Original Message-----
>> From: tsuna [mailto:[email protected]]
>> Sent: Friday, January 28, 2011 12:14 PM
>> To: [email protected]
>> Subject: Re: Row Keys
>>
>> On Fri, Jan 28, 2011 at 12:09 PM, Peter Haidinyak <[email protected]>
>> wrote:
>> >        This is going to seem like a dumb question but it is recommended
>> that you use a random key to spread the insert/read load among your region
>> servers. My question is if I am using a scan with startrow and endrow  how
>> does that work with random row keys?
>>
>> The keys are always sorted.  So if you generate random keys, you'll
>> get your data back in a random order.
>> What is recommended depends on the specific problem you're trying to
>> solve.  But generally, one of the strengths of HBase is that the rows
>> are sorted, so sequential scanning is efficient (thanks to data
>> locality).
>>
>> --
>> Benoit "tsuna" Sigoure
>> Software Engineer @ www.StumbleUpon.com
>>
>
>

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