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HBase, mail # user - Long row + column keys


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Varun Sharma 2012-12-03, 19:58
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Re: Long row + column keys
Marcos Ortiz 2012-12-03, 20:36
Regards, Varun.
I think that you can see the Bernoit Sigoure (@tsuna)�s talk called
"Lessons learned from OpenTSDB" in the last
HBaseCon . [1]
He explained in great detail how to design your schema to obtain the
best performance from HBase.

Other recommended talks are: "HBase Internals" from Lars, and "HBase
Schema Design" from Ian
[2][3]

[1] http://www.slideshare.net/cloudera/4-opentsdb-hbasecon
[2]
http://www.slideshare.net/cloudera/3-learning-h-base-internals-lars-hofhansl-salesforce-final/
[3] http://www.slideshare.net/cloudera/5-h-base-schemahbasecon2012

On 12/03/2012 02:58 PM, Varun Sharma wrote:
> Hi,
>
> I have a schema where the rows are 8 bytes long and the columns are 12
> bytes long (roughly 1000 columns per row). The value is 0 bytes. Is this
> going to be space inefficient in terms of HFile size (large index + blocks)
> ? The total key size, as far as i know, would be 8 + 12 + 8 (timestamp) > 28 bytes. I am using hbase 0.94.0 which has HFile v2.
Yes, like you said, HFile v2 is included in 0.94, but although is in
trunk right now, your should
keep following the development of HBase, focused on HBASE-5313 and
HBASE-5521, because
the development team is working in a new file storage format called
HFile v3, based on a columnar
format called Trevni for Avro by Dug Cutting.[4][5][6][7]
[4] https://issues.apache.org/jira/browse/HBASE-5313
[5] https://issues.apache.org/jira/browse/HBASE-5521
[6] https://github.com/cutting/trevni
[7] https://issues.apache.org/jira/browse/AVRO-806
>
> Also, should I be using an encoding technique to get the number of bytes
> down (like PrefixDeltaEncoding) which is provided by hbase ?
Read the Cloudera�s blog post called "HBase I/O - HFile" to see how
Prefix and Diff encodings
works, and decide which is the more suitable for you.[8]
[8] http://blog.cloudera.com/blog/2012/06/hbase-io-hfile-input-output/

I hope that all this information could help you.
Best wishes
>
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Varun Sharma 2012-12-03, 21:06
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Anoop Sam John 2012-12-04, 04:23
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Varun Sharma 2012-12-04, 05:48