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From James Taylor <jamestay...@apache.org>
Subject Re: Column Cardinality and Stats table as an "interface"
Date Thu, 14 Apr 2016 19:24:28 GMT
FYI, Lars H. is looking at PHOENIX-258 for improving performance of
DISTINCT. We don't yet keep any cardinality info in our stats
(see PHOENIX-1178).

Thanks,
James

On Thu, Apr 14, 2016 at 11:22 AM, Nick Dimiduk <ndimiduk@gmail.com> wrote:

> Hello,
>
> I'm curious if there are any tricks for estimating the cardinality of the
> values in a phoenix column. Even for leading rowkey column, a select
> distinct query on a large table requires a full scan (PHOENIX-258). Maybe
> one could reach into the stats table and derive some knowledge? How much of
> a "bad thing" would this be?
>
> Thanks,
> Nick
>

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