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From Lars George <lars.geo...@gmail.com>
Subject Re: Newbie question about scan filters
Date Sun, 05 Dec 2010 18:05:08 GMT
Hi Hari,

The filters are applied server side (aka predicate pushdown). If you
were to scan and skip you incur extra IO cost. Filters, as they are
implemented right now are simply skipping and therefore all they can
do is slightly improve a normal scan performance. In the future you
might get better performance as they are re-implemented as
Coprocessors. Also, depending on certain filter criteria we can
optimize scans by skipping entire store files (since we know it does
not certain keys or timestamp based values).

Lars

On Sun, Dec 5, 2010 at 6:39 PM, Hari Sreekumar <hsreekumar@clickable.com> wrote:
> Hi
>
> What are the differences between using a scan filter and simpli
> scanning and then filtering using if conditions? Any particular
> gotchas you need to be careful about while using filters extensively?
>
> Hari
>

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