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https://issues.apache.org/jira/browse/LUCENE-2810?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12970882#action_12970882
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Robert Muir commented on LUCENE-2810:
-------------------------------------

bq. Again, you seem to be hung up on the word compression, so let's stop using 
it. I'm not necessarily talking about compression here, OK

To me its compression either way, you can call it data deduplication if you 
want (modern filesystems do this too!).

bq. especially since retrieving stored fields is almost always one of the 
biggest performance killers in real world applications.

I haven't had this experience, please don't try to generalize for everyone.


> Explore Alternate Stored Field approaches for highly redundant data
> -------------------------------------------------------------------
>
>                 Key: LUCENE-2810
>                 URL: https://issues.apache.org/jira/browse/LUCENE-2810
>             Project: Lucene - Java
>          Issue Type: Improvement
>          Components: Store
>            Reporter: Grant Ingersoll
>            Assignee: Grant Ingersoll
>
> In some cases (logs, HTML pages w/ boilerplate, etc.), the stored fields for 
> documents contain a lot of redundant information and end up wasting a lot of 
> space across a large collection of documents.  For instance, simply 
> compressing a typical log file often results in > 75% compression rates.  We 
> should explore mechanisms for applying compression across all the documents 
> for a field (or fields) while still maintaining relatively fast lookup (that 
> being said, in most logging applications, fast retrieval of a given event is 
> not always critical.)  For instance, perhaps it is possible to have a part of 
> storage that contains the set of unique values for all the fields and the 
> document field value simply contains a reference (could be as small as a few 
> bits depending on the number of uniq. items) to that value instead of having 
> a full copy.  Extending this, perhaps we can leverage some existing 
> compression capabilities in Java to provide this as well.  
> It may make sense to implement this as a Directory, but it might also make 
> sense as a Codec, if and when we have support for changing storage Codecs.

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