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RE: Column Qualifier space requirements
>It means that in order to save space I need to use smallest Column
Qualifier (and sometimes it makes sense)...
Yes
>However, why Column Family (byte array) is repeated for each KeyValue? Is
it physically repeated for each cell?
Yes CF byte[] also physically stored in every cell (every KV)..  At the storage level HBase deals with KVs and every KV is having a full identity of its.[rowkey+cf+qualifier+timestamp]

If you are working with 0.94 versions there is one optimization done wrt space saving. This is known as block level encoding. See the interface DataBlockEncoder and diff implementations available for it...

-Anoop-
________________________________________
From: Fuad Efendi [[EMAIL PROTECTED]]
Sent: Tuesday, October 02, 2012 2:40 AM
To: [EMAIL PROTECTED]
Subject: Re: Column Qualifier space requirements

Thanks;

It means that in order to save space I need to use smallest Column
Qualifier (and sometimes it makes sense)...

However, why Column Family (byte array) is repeated for each KeyValue? Is
it physically repeated for each cell?
>
>Hi there, take a look at the Hbase Refguide here...
>
>http://hbase.apache.org/book.html#regions.arch
>
>For this section...
>
>9.7.5.4. KeyValue
>
>
>
>
>
>>Hi,
>>
>>Is column qualifier physically stored in a Cell? Or pointer to it? Do we
>>need to care about long size such as
>>my_very_long_qualifier:1
>>
>>(size of a value is small in comparison to size of qualifierÅ )
>>
>>thanks
>>
>>
>
>