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From Chris Hostetter <hossman_luc...@fucit.org>
Subject Re: Applying filter re-searches?
Date Tue, 19 Sep 2006 21:33:20 GMT

:   I am looking a bit at the source code and there's something that's
: puzzling me. It looks like filtering a query reexecutes it, but this
: time applying the filter. Not applying the filter to some results
: stored with the query.
:   If this is true, I fail to see the point of having filters, instead
: of just building a bigger query.

the main advantage is that Filter's don't affect the scores of the Query
itself.  A secondary advantage is that a Filter can be cached, so that
the computation necceessary for complex Filter can be done only once --
that wouldn't be possible with most Query types.



(there are also some changes in the works that will allow a Searcher to
look at what is matched by the Filter and skip scoring matches to the
Query that the Filter will weed out -- but this is just a hypothetical
benefit that doesn't exist yet)



:
: Thanks
:
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-Hoss


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