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https://issues.apache.org/jira/browse/LUCENE-5938?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14129937#comment-14129937
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Robert Muir commented on LUCENE-5938:
-------------------------------------

This also sounds like a very good candidate for MultiTermQueryWrapperFilter 
(used by "filter" rewrite)? 

I think last i looked, the main downside to filter rewrite is for sparse 
queries. Because of this, its faster for those queries to do a boolean rewrite, 
and there is complex logic ("auto rewrite") that first rewrites as 
booleanquery, then if it hits too many terms / too much density it "starts 
over" as filter rewrite. Perhaps we can just replace all of that with this 
bitset?

> New DocIdSet implementation with random write access
> ----------------------------------------------------
>
>                 Key: LUCENE-5938
>                 URL: https://issues.apache.org/jira/browse/LUCENE-5938
>             Project: Lucene - Core
>          Issue Type: Improvement
>            Reporter: Adrien Grand
>            Assignee: Adrien Grand
>         Attachments: LUCENE-5938.patch
>
>
> We have a great cost API that is supposed to help make decisions about how to 
> best execute queries. However, due to the fact that several of our filter 
> implementations (eg. TermsFilter and BooleanFilter) return FixedBitSets, 
> either we use the cost API and make bad decisions, or need to fall back to 
> heuristics which are not as good such as 
> RandomAccessFilterStrategy.useRandomAccess which decides that random access 
> should be used if the first doc in the set is less than 100.
> On the other hand, we also have some nice compressed and cacheable DocIdSet 
> implementation but we cannot make use of them because TermsFilter requires a 
> DocIdSet that has random write access, and FixedBitSet is the only DocIdSet 
> that we have that supports random access.
> I think it would be nice to replace FixedBitSet in those filters with another 
> DocIdSet that would also support random write access but would have a better 
> cost?



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