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From Doug Meil <doug.m...@explorysmedical.com>
Subject Re: Hbase Schema
Date Wed, 11 Jul 2012 19:59:05 GMT

re:  Q2

Yes you can have the same CF name in different tables.  Column Family
names are embedded in each KeyValue.

See:  http://hbase.apache.org/book.html#regions.arch  for more detail

re:  Q3

It depends on what you you need.  A common pattern is using composite keys
where the lead portion represents some natural grouping of data (e.g., a
userid) but that is also hashed to provide distribution across the cluster.

re:  Q4

Read the RefGuide! 

http://hbase.apache.org/book.html




On 7/11/12 3:16 PM, "grashmi13" <rashmi.maheshwari@rsystems.com> wrote:

>
>Hi,
>
>In RDBMS we have multiple DB schemas\oracle user instances.
>
>Similarly, can we have multiple db schemas in hbase? If yes, can we have
>multiple schemas one one hadoop-hbase cluster? If multiple schemas
>possible,
>how can we define them? Using configuration or programatically?
>
>Q2: can we have same column family name in multiple tables? if yes, does
>it
>impacts performance if we have same name column family in multiple tables?
>
>Q3: Sequential keys improves read performance and random keys improves
>write
>performance. which way one must go?
>
>Q4: What are best practices to improve hadoop+hbase performance?
>
>Q5: when one program is deleting tables, another program is accessing a
>row
>of that table. what would be impact of it? can we have some sort of lock
>while reading or while deleting a table?
>
>Q6: as everything in application is byte form, what would happen if hbase
>db
>and application are using different character set? can we synch both for
>some particular character set by configuration or programatically?
>-- 
>View this message in context:
>http://old.nabble.com/Hbase-Schema-tp34147582p34147582.html
>Sent from the HBase User mailing list archive at Nabble.com.



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