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https://issues.apache.org/jira/browse/LUCENE-6458?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14519402#comment-14519402
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David Smiley commented on LUCENE-6458:
--------------------------------------

bq. Maybe we could change TermsQuery.rewrite to rewrite to a boolean query 
(wrapped in a CSQ) when there are few terms? This would avoid having to worry 
about this in every query parser.

You read my mind ;-)  I had that thought right after I posted.

bq. In my opinion, the issue with rewriting to a BooleanQuery is that its 
scorer needs to rebalance the priority queue whenever it advances, which is 
O(log(#clauses)). So it gets slower as you add new optional clauses while the 
way TermsQuery works doesn't care much about the number of matching terms. I 
don't think the total number of index terms is relevant?

Ah; I haven't looked in a while so I didn't know about the priority-queue over 
there in BooleanQuery (DisjunctionScorer actually).  Never mind.

> MultiTermQuery's FILTER rewrite method should support skipping whenever 
> possible
> --------------------------------------------------------------------------------
>
>                 Key: LUCENE-6458
>                 URL: https://issues.apache.org/jira/browse/LUCENE-6458
>             Project: Lucene - Core
>          Issue Type: Improvement
>            Reporter: Adrien Grand
>            Assignee: Adrien Grand
>            Priority: Minor
>         Attachments: LUCENE-6458.patch
>
>
> Today MultiTermQuery's FILTER rewrite always builds a bit set fom all 
> matching terms. This means that we need to consume the entire postings lists 
> of all matching terms. Instead we should try to execute like regular 
> disjunctions when there are few terms.



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