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Re: Custom versioning best practices
Hello Michael,

Thank you for your response.

By the way, is it possible to set setMaxVersions per column family on a
scan?

/David
On Thu, Nov 22, 2012 at 5:11 PM, Michael Segel <[EMAIL PROTECTED]>wrote:

> IMHO, the best practice is not to do this.
>
> Its an abuse of versioning and if you really want to store temporal data,
> make it part of the column name.
>
>
> On Nov 22, 2012, at 7:55 AM, David Koch <[EMAIL PROTECTED]> wrote:
>
> > Hello,
> >
> > I was thinking of using versions with custom timestamps to store the
> > evolution of a column value - as opposed to creating several (time_t,
> > value_at_time_t) qualifier-value pairs. The value to be stored is a
> single
> > integer. Fast ad-hoc retrieval of multiple versions based on a row key +
> > filter [1] (i.e through a web service) is important, the number of row
> keys
> > will be between 10^6 and 10^9.
> >
> > a) If the number of versions (timestamps) is moderate, can I expect
> > read/filtering performance to be better than when using multiple
> > qualifier/value pairs?
> > b) For a larger number of versions, say 365, what if any precautions
> should
> > I take with respect to the HBase/table setup.
> >
> > I looked around a bit and found the following:
> >
> > The documentation [2] mentions that the maximum number of versions should
> > not be too high ("in the hundreds"). The HBase o'Reilly book [3] on the
> > other hand mentions that Facebook use(d) versions to store inbox messages
> > in order. Clearly, the number of messages may grow quite large (>> 100).
> Is
> > [1] still valid with more recent versions of HBase?
> >
> > Thank you,
> >
> > /David
> >
> > [1]
> >
> http://hbase.apache.org/apidocs/org/apache/hadoop/hbase/filter/TimestampsFilter.html
> > [2] http://hbase.apache.org/book/schema.versions.html
> > [3] 1st edition, page 384
>
>