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From Anoop Sam John <anoo...@huawei.com>
Subject RE: Column Qualifier space requirements
Date Wed, 03 Oct 2012 05:47:56 GMT
>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 [fuad@efendi.ca]
Sent: Tuesday, October 02, 2012 2:40 AM
To: user@hbase.apache.org
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 qualifierĊ )
>>
>>thanks
>>
>>
>
>
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