# Percolator and CustomMemoryIndex

**URL:** <https://discuss.elastic.co/t/percolator-and-custommemoryindex/4258>\
**Category:** Elasticsearch\
**Created:** [April 19, 2011, 9:17pm UTC](https://discuss.elastic.co/t/percolator-and-custommemoryindex/4258 "2011-04-19T21:17:32Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![otisg](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/otisg/32/492_2.png) [@otisg](https://discuss.elastic.co/u/otisg)\
**Post date:** [April 19, 2011, 9:17pm UTC](https://discuss.elastic.co/t/percolator-and-custommemoryindex/4258/1 "2011-04-19T21:17:32Z")

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Hi,

I was looking at Percolator and noticed CustomMemoryIndex.

1. What's custom about this CustomMemoryIndex? Did something not work  
well with the original MemoryIndex? I looked for comments in the code  
that might indicate what was changed and why, but there aren't any  
such comments there.

2. There are 2 license headers in there.

## Thanks, Otis

Sematext :: [http://sematext.com/](http://sematext.com/) :: Solr - Lucene - Nutch  
Lucene ecosystem search :: [http://search-lucene.com/](http://search-lucene.com/)

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**Author:** ![kimchy](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/kimchy/32/44952_2.png) [@kimchy](https://discuss.elastic.co/u/kimchy)\
**Post date:** [April 19, 2011, 11:26pm UTC](https://discuss.elastic.co/t/percolator-and-custommemoryindex/4258/2 "2011-04-19T23:26:55Z")

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CustomMemoryIndex allows to index the same field several times, which is not allowed in the default MemoryIndex. Planning on submitting a patch post 0.16.  
On Wednesday, April 20, 2011 at 12:17 AM, Otis wrote:

> Hi,
> 
> I was looking at Percolator and noticed CustomMemoryIndex.
> 
> 1. What's custom about this CustomMemoryIndex? Did something not work  
> well with the original MemoryIndex? I looked for comments in the code  
> that might indicate what was changed and why, but there aren't any  
> such comments there.
> 
> 2. There are 2 license headers in there.
> 
> ## Thanks, Otis
> 
> Sematext :: [http://sematext.com/](http://sematext.com/) :: Solr - Lucene - Nutch  
> Lucene ecosystem search :: [http://search-lucene.com/](http://search-lucene.com/)

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<div class="post-metadata">

**Author:** ![otisg](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/otisg/32/492_2.png) [@otisg](https://discuss.elastic.co/u/otisg)\
**Post date:** [April 20, 2011, 2:56pm UTC](https://discuss.elastic.co/t/percolator-and-custommemoryindex/4258/3 "2011-04-20T14:56:10Z")

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Thanks for anticipating my next question 😉

I was wondering if you hit the problem described in  
[http://search-lucene.com/m/rZpRR1lYdZ32&subj=MemoryIndex+Reader+IndexReader+and+SegmentReader](http://search-lucene.com/m/rZpRR1lYdZ32&subj=MemoryIndex+Reader+IndexReader+and+SegmentReader)  
and whether you made any changes to MemoryIndex in your  
CustomMemoryIndex to avoid them. Sounds like you had no issues with  
MemoryIndex and it supported all query types you tried?

## Otis

We're hiring HBase hackers for Data Mining and Analytics

> **[Jobs](https://sematext.com/jobs/)**
>
> We’re Hiring We are always looking for smart, passionate, motivated, and independent people regardless of where on the planet they may be. Learn more about the company Agent & Backend Engineer Full Stack Developer Backend Engineer Frontend...

On Apr 19, 7:26 pm, Shay Banon [shay.ba...@elasticsearch.com](mailto:shay.ba...@elasticsearch.com) wrote:

> CustomMemoryIndex allows to index the same field several times, which is not allowed in the default MemoryIndex. Planning on submitting a patch post 0.16.
> 
> On Wednesday, April 20, 2011 at 12:17 AM, Otis wrote:
> 
> > Hi,
> 
> > I was looking at Percolator and noticed CustomMemoryIndex.
> 
> > 1. What's custom about this CustomMemoryIndex? Did something not work  
> > well with the original MemoryIndex? I looked for comments in the code  
> > that might indicate what was changed and why, but there aren't any  
> > such comments there.
> 
> > 1. There are 2 license headers in there.
> 
> > ## Thanks, Otis
> > 
> > Sematext ::[http://sematext.com/::](http://sematext.com/::) Solr - Lucene - Nutch  
> > Lucene ecosystem search ::[http://search-lucene.com/](http://search-lucene.com/)

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<div class="post-metadata">

**Author:** ![system](https://us1.discourse-cdn.com/elastic/original/3X/1/a/1ac57faf039f6b580b3f104ef42a2a89e41014de.png) [@system](https://discuss.elastic.co/u/system)\
**Post date:** [July 6, 2017, 4:08am UTC](https://discuss.elastic.co/t/percolator-and-custommemoryindex/4258/4 "2017-07-06T04:08:00Z")

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Closed on July 6, 2017, 4:08am UTC