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https://issues.apache.org/jira/browse/LUCENE-4872?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13614514#comment-13614514
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Simon Willnauer commented on LUCENE-4872:
-----------------------------------------
I often use min_should_match in practice. Like one example is if you do search
for titles or name like POI's or meta-data. Lets take youtube as an example you
often get queries like "queen wembley live 1989" which was in-fact 1986 (at
least the one I meant here) a pretty good pattern is to use some metric like
80% must match if >= 2 query terms etc.
Another good example is if you use shingles a query like "queen wembley live
1989" produces lots of terms and "wembley live" might be pretty common so you
want to make sure that you are not returning stuff from other band but on the
other hand a pure conjunction is not acceptable here either.
hope that give some insight?
> BooleanWeight should decide how to execute minNrShouldMatch
> -----------------------------------------------------------
>
> Key: LUCENE-4872
> URL: https://issues.apache.org/jira/browse/LUCENE-4872
> Project: Lucene - Core
> Issue Type: Sub-task
> Components: core/search
> Reporter: Robert Muir
> Fix For: 5.0, 4.3
>
> Attachments: crazyMinShouldMatch.tasks
>
>
> LUCENE-4571 adds a dedicated document-at-time scorer for minNrShouldMatch
> which can use advance() behind the scenes.
> In cases where you have some really common terms and some rare ones this can
> be a huge performance improvement.
> On the other hand BooleanScorer might still be faster in some cases.
> We should think about what the logic should be here: one simple thing to do
> is to always use the new scorer when minShouldMatch is set: thats where i'm
> leaning.
> But maybe we could have a smarter heuristic too, perhaps based on cost()
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