# Doing bounding box filtering using a geohash prefix

**URL:** <https://discuss.elastic.co/t/doing-bounding-box-filtering-using-a-geohash-prefix/11030>\
**Category:** Elasticsearch\
**Created:** [March 6, 2013, 8:57am UTC](https://discuss.elastic.co/t/doing-bounding-box-filtering-using-a-geohash-prefix/11030 "2013-03-06T08:57:31Z")\
**Posts on this page:** 11\
**Page:** 1

<div class="post-metadata">

**Author:** ![Gian\_Luca\_Ortelli](https://avatars.discourse-cdn.com/v4/letter/g/e68b1a/32.png) [@Gian\_Luca\_Ortelli](https://discuss.elastic.co/u/Gian_Luca_Ortelli)\
**Post date:** [March 6, 2013, 8:57am UTC](https://discuss.elastic.co/t/doing-bounding-box-filtering-using-a-geohash-prefix/11030/1 "2013-03-06T08:57:31Z")

</div>

Hi,

I read on the docs that you can define the bounding box using 2 geohash  
values for the top left and bottom right corners. Is there a way to specify  
the bounding box using a single geohash value? Typically, it would be a  
value with less than 12 chars, to search all the documents containing it as  
a prefix.

Thanks,  
Gianluca

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**Author:** ![Jilles\_van\_Gurp](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/jilles_van_gurp/32/879_2.png) [@Jilles\_van\_Gurp](https://discuss.elastic.co/u/Jilles_van_Gurp)\
**Post date:** [March 6, 2013, 9:18am UTC](https://discuss.elastic.co/t/doing-bounding-box-filtering-using-a-geohash-prefix/11030/2 "2013-03-06T09:18:08Z")

</div>

No, not really. The way geohashes work is that they are pretty much  
rectangular themselves. So shortening the geohash prefix increases the size  
of the rectangle. The problem is that you can't move them around. So, you'd  
need multiple geohashes to cover an arbitrary bounding box unless the  
bounding box happens to overlap exactly with a single geohash..

What you can do is calculate the set of geohashes that cover a particular  
boundingbox (or any polygon) and use smaller prefixes to cover the insides  
and larger ones for the boundaries. That is pretty much what geo\_shape does  
but you can also do it manually and associate the geohashes with a field.  
Then you simply use prefix queries to search for anything that overlaps  
with the shape.

I've done this before and I have a library to support the geohash  
manipulation: [GitHub - jillesvangurp/geotools](https://github.com/jillesvangurp/geotools)

Jilles

On Wednesday, March 6, 2013 9:57:31 AM UTC+1, Gian Luca Ortelli wrote:

> Hi,
> 
> I read on the docs that you can define the bounding box using 2 geohash  
> values for the top left and bottom right corners. Is there a way to specify  
> the bounding box using a single geohash value? Typically, it would be a  
> value with less than 12 chars, to search all the documents containing it as  
> a prefix.
> 
> Thanks,  
> Gianluca

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**Author:** ![Gian\_Luca\_Ortelli](https://avatars.discourse-cdn.com/v4/letter/g/e68b1a/32.png) [@Gian\_Luca\_Ortelli](https://discuss.elastic.co/u/Gian_Luca_Ortelli)\
**Post date:** [March 6, 2013, 10:05am UTC](https://discuss.elastic.co/t/doing-bounding-box-filtering-using-a-geohash-prefix/11030/3 "2013-03-06T10:05:07Z")

</div>

Hi,

luckily I don't have the need to cover arbitrary bounding boxes; because of  
how my application works, the rectangle defined by a geohash prefix IS my  
bounding box.

My problem is with the exact construction of the query; you mention prefix  
queries, but I guess I should index the geohash as a normal field to use  
them, right? I'm wondering if there is a way to search directly on the  
geopoint field, like a variant of the bounding box syntax. Are you aware of  
anything like that?

Thanks,  
Gianluca

On Wednesday, March 6, 2013 10:18:08 AM UTC+1, Jilles van Gurp wrote:

> No, not really. The way geohashes work is that they are pretty much  
> rectangular themselves. So shortening the geohash prefix increases the size  
> of the rectangle. The problem is that you can't move them around. So, you'd  
> need multiple geohashes to cover an arbitrary bounding box unless the  
> bounding box happens to overlap exactly with a single geohash..
> 
> What you can do is calculate the set of geohashes that cover a particular  
> boundingbox (or any polygon) and use smaller prefixes to cover the insides  
> and larger ones for the boundaries. That is pretty much what geo\_shape does  
> but you can also do it manually and associate the geohashes with a field.  
> Then you simply use prefix queries to search for anything that overlaps  
> with the shape.
> 
> I've done this before and I have a library to support the geohash  
> manipulation: [GitHub - jillesvangurp/geotools](https://github.com/jillesvangurp/geotools)
> 
> Jilles
> 
> On Wednesday, March 6, 2013 9:57:31 AM UTC+1, Gian Luca Ortelli wrote:
> 
> > Hi,
> > 
> > I read on the docs that you can define the bounding box using 2 geohash  
> > values for the top left and bottom right corners. Is there a way to specify  
> > the bounding box using a single geohash value? Typically, it would be a  
> > value with less than 12 chars, to search all the documents containing it as  
> > a prefix.
> > 
> > Thanks,  
> > Gianluca

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**Author:** ![Jilles\_van\_Gurp](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/jilles_van_gurp/32/879_2.png) [@Jilles\_van\_Gurp](https://discuss.elastic.co/u/Jilles_van_Gurp)\
**Post date:** [March 6, 2013, 10:13am UTC](https://discuss.elastic.co/t/doing-bounding-box-filtering-using-a-geohash-prefix/11030/4 "2013-03-06T10:13:18Z")

</div>

I haven't got any experience with the geopoint type. I guess in principle  
it should be possible to query a lucene field directly though I'm not sure  
how this would work in Elasticsearch. At the lucene level, there are no  
field types: it's all just terms. You may need to write some plugin to get  
to the lucene field directly.

But it is probably easier to just add the geohash as a string field and  
search on that. You can use prefix, term, wild card queries etc. and it  
should just work.

Jilles

On Wednesday, March 6, 2013 11:05:07 AM UTC+1, Gian Luca Ortelli wrote:

> Hi,
> 
> luckily I don't have the need to cover arbitrary bounding boxes; because  
> of how my application works, the rectangle defined by a geohash prefix IS  
> my bounding box.
> 
> My problem is with the exact construction of the query; you mention prefix  
> queries, but I guess I should index the geohash as a normal field to use  
> them, right? I'm wondering if there is a way to search directly on the  
> geopoint field, like a variant of the bounding box syntax. Are you aware of  
> anything like that?
> 
> Thanks,  
> Gianluca
> 
> On Wednesday, March 6, 2013 10:18:08 AM UTC+1, Jilles van Gurp wrote:
> 
> > No, not really. The way geohashes work is that they are pretty much  
> > rectangular themselves. So shortening the geohash prefix increases the size  
> > of the rectangle. The problem is that you can't move them around. So, you'd  
> > need multiple geohashes to cover an arbitrary bounding box unless the  
> > bounding box happens to overlap exactly with a single geohash..
> > 
> > What you can do is calculate the set of geohashes that cover a particular  
> > boundingbox (or any polygon) and use smaller prefixes to cover the insides  
> > and larger ones for the boundaries. That is pretty much what geo\_shape does  
> > but you can also do it manually and associate the geohashes with a field.  
> > Then you simply use prefix queries to search for anything that overlaps  
> > with the shape.
> > 
> > I've done this before and I have a library to support the geohash  
> > manipulation: [GitHub - jillesvangurp/geotools](https://github.com/jillesvangurp/geotools)
> > 
> > Jilles
> > 
> > On Wednesday, March 6, 2013 9:57:31 AM UTC+1, Gian Luca Ortelli wrote:
> > 
> > > Hi,
> > > 
> > > I read on the docs that you can define the bounding box using 2 geohash  
> > > values for the top left and bottom right corners. Is there a way to specify  
> > > the bounding box using a single geohash value? Typically, it would be a  
> > > value with less than 12 chars, to search all the documents containing it as  
> > > a prefix.
> > > 
> > > Thanks,  
> > > Gianluca

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**Author:** ![Gian\_Luca\_Ortelli](https://avatars.discourse-cdn.com/v4/letter/g/e68b1a/32.png) [@Gian\_Luca\_Ortelli](https://discuss.elastic.co/u/Gian_Luca_Ortelli)\
**Post date:** [March 6, 2013, 11:01am UTC](https://discuss.elastic.co/t/doing-bounding-box-filtering-using-a-geohash-prefix/11030/5 "2013-03-06T11:01:12Z")

</div>

Thanks Jilles,

I'll go with a normal query then.

Gianluca

On Wednesday, March 6, 2013 11:13:18 AM UTC+1, Jilles van Gurp wrote:

> I haven't got any experience with the geopoint type. I guess in principle  
> it should be possible to query a lucene field directly though I'm not sure  
> how this would work in Elasticsearch. At the lucene level, there are no  
> field types: it's all just terms. You may need to write some plugin to get  
> to the lucene field directly.
> 
> But it is probably easier to just add the geohash as a string field and  
> search on that. You can use prefix, term, wild card queries etc. and it  
> should just work.
> 
> Jilles
> 
> On Wednesday, March 6, 2013 11:05:07 AM UTC+1, Gian Luca Ortelli wrote:
> 
> > Hi,
> > 
> > luckily I don't have the need to cover arbitrary bounding boxes; because  
> > of how my application works, the rectangle defined by a geohash prefix IS  
> > my bounding box.
> > 
> > My problem is with the exact construction of the query; you mention  
> > prefix queries, but I guess I should index the geohash as a normal field to  
> > use them, right? I'm wondering if there is a way to search directly on the  
> > geopoint field, like a variant of the bounding box syntax. Are you aware of  
> > anything like that?
> > 
> > Thanks,  
> > Gianluca
> > 
> > On Wednesday, March 6, 2013 10:18:08 AM UTC+1, Jilles van Gurp wrote:
> > 
> > > No, not really. The way geohashes work is that they are pretty much  
> > > rectangular themselves. So shortening the geohash prefix increases the size  
> > > of the rectangle. The problem is that you can't move them around. So, you'd  
> > > need multiple geohashes to cover an arbitrary bounding box unless the  
> > > bounding box happens to overlap exactly with a single geohash..
> > > 
> > > What you can do is calculate the set of geohashes that cover a  
> > > particular boundingbox (or any polygon) and use smaller prefixes to cover  
> > > the insides and larger ones for the boundaries. That is pretty much what  
> > > geo\_shape does but you can also do it manually and associate the geohashes  
> > > with a field. Then you simply use prefix queries to search for anything  
> > > that overlaps with the shape.
> > > 
> > > I've done this before and I have a library to support the geohash  
> > > manipulation: [GitHub - jillesvangurp/geotools](https://github.com/jillesvangurp/geotools)
> > > 
> > > Jilles
> > > 
> > > On Wednesday, March 6, 2013 9:57:31 AM UTC+1, Gian Luca Ortelli wrote:
> > > 
> > > > Hi,
> > > > 
> > > > I read on the docs that you can define the bounding box using 2 geohash  
> > > > values for the top left and bottom right corners. Is there a way to specify  
> > > > the bounding box using a single geohash value? Typically, it would be a  
> > > > value with less than 12 chars, to search all the documents containing it as  
> > > > a prefix.
> > > > 
> > > > Thanks,  
> > > > Gianluca

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**Author:** ![David\_Smiley](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/david_smiley/32/2451_2.png) [@David\_Smiley](https://discuss.elastic.co/u/David_Smiley)\
**Post date:** [March 6, 2013, 8:09pm UTC](https://discuss.elastic.co/t/doing-bounding-box-filtering-using-a-geohash-prefix/11030/6 "2013-03-06T20:09:41Z")

</div>

Hi Jilles,

I'm David Smiley, committer on Lucene/Solr specializing in spatial. I did  
much of the spatial implementation that I believe Elasticsearch now uses.  
Jilles, are there spatial features that Elasticsearch isn't offering that  
require you to work with geohashes & what'not at the user level as you  
describe? If so, perhaps these use-cases are en-route to Elasticsearch via  
Lucene up-stream eventually, and if not then maybe you should add feature  
requests so they get tracked and eventually implemented. I think geohashes  
are neat but an implementation detail that you wouldn't even have to be  
aware of if the search platform has all the spatial features you need.

p.s. I'll have to look at your "geotools" (not to be confused with _the_  
GeoTools at [geotools.org](http://geotools.org)) some time, for possible re-use of relevant  
algorithms in Spatial4j (the spatial dependency of Lucene-spatial that I  
work on).

Cheers,  
David Smiley

On Wednesday, March 6, 2013 4:18:08 AM UTC-5, Jilles van Gurp wrote:

> No, not really. The way geohashes work is that they are pretty much  
> rectangular themselves. So shortening the geohash prefix increases the size  
> of the rectangle. The problem is that you can't move them around. So, you'd  
> need multiple geohashes to cover an arbitrary bounding box unless the  
> bounding box happens to overlap exactly with a single geohash..
> 
> What you can do is calculate the set of geohashes that cover a particular  
> boundingbox (or any polygon) and use smaller prefixes to cover the insides  
> and larger ones for the boundaries. That is pretty much what geo\_shape does  
> but you can also do it manually and associate the geohashes with a field.  
> Then you simply use prefix queries to search for anything that overlaps  
> with the shape.
> 
> I've done this before and I have a library to support the geohash  
> manipulation: [GitHub - jillesvangurp/geotools](https://github.com/jillesvangurp/geotools)
> 
> Jilles
> 
> On Wednesday, March 6, 2013 9:57:31 AM UTC+1, Gian Luca Ortelli wrote:
> 
> > Hi,
> > 
> > I read on the docs that you can define the bounding box using 2 geohash  
> > values for the top left and bottom right corners. Is there a way to specify  
> > the bounding box using a single geohash value? Typically, it would be a  
> > value with less than 12 chars, to search all the documents containing it as  
> > a prefix.
> > 
> > Thanks,  
> > Gianluca

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**Author:** ![Jilles\_van\_Gurp](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/jilles_van_gurp/32/879_2.png) [@Jilles\_van\_Gurp](https://discuss.elastic.co/u/Jilles_van_Gurp)\
**Post date:** [March 6, 2013, 10:39pm UTC](https://discuss.elastic.co/t/doing-bounding-box-filtering-using-a-geohash-prefix/11030/7 "2013-03-06T22:39:13Z")

</div>

Hi David,

I think Elasticsearch is nearly offering what I need but not quite yet. On  
paper it looks all good with support for all of the relevant different  
shapes. Part of my problem has been figuring out what exactly there is,  
what actually works, how it works, and what the current state is in terms  
of maturity, performance, etc. The documentation is a bit of a mixed bag  
currently and I'm not that familiar with the Elasticsearch code base that  
I can easily make sense of what it is trying to do. That also puts me in an  
awkward position with respect to suggesting changes since I can't really  
speak authoritatively on what it does right now. This is not an easy code  
base to work with currently.

The geo\_shape functionality in Elasticsearch looks promising but at the  
same time there have been major changes to it very recently, which worries  
me since it indicates the design is a bit in flux right now and it is  
unclear where things are going.

My recent experiments with using geo\_shape and intersects indicate that  
there seems to be accuracy problems that need work. I think mostly these  
are known issues already. Particularly, I'm getting false negatives on some  
queries and other people have reported false positives. Another issue in  
Elasticsearch is that I think there needs to be an effort to unify the  
geo\_shape and geo\_point types. I don't see a good reason for having two  
types here, especially since both seem to lack features that the other has.

I'm aware that my choice of geotools as a name was a bit unfortunate given  
the other project with the same name. I might have to rename it ;-). My  
intention with it was to keep things simple and implement some generic  
things that I need to implement geospatial search. In my view this is a  
very simple problem: given a shape, cover it with geohashes, index them and  
use wildcard queries to find things back. You don't even need Lucene for  
this and I have used a similar approach with mysql and couchdb in the past.

One of my goals was to avoid coming up with yet another Point, Polygon,  
etc. class hierarchy and instead try to imitate the geojson model of simply  
using multi dimensional arrays of doubles to represent points, lines,  
polygons, etc. The algorithms are mostly just scavenged and adapted from  
different sources. This has the advantage of avoiding a lot of work  
translating one object model to another (impedence mismatch) and also  
minimizes the memory used. That last point is important for me since I use  
this library for data processing as well on a pretty large scale.

In any case, if you find something of use please use it. I'll be happy to  
assist you integrating/refactoring if needed.

Jilles

On Wednesday, March 6, 2013 9:09:41 PM UTC+1, David Smiley wrote:

> Hi Jilles,
> 
> I'm David Smiley, committer on Lucene/Solr specializing in spatial. I did  
> much of the spatial implementation that I believe Elasticsearch now uses.  
> Jilles, are there spatial features that Elasticsearch isn't offering that  
> require you to work with geohashes & what'not at the user level as you  
> describe? If so, perhaps these use-cases are en-route to Elasticsearch via  
> Lucene up-stream eventually, and if not then maybe you should add feature  
> requests so they get tracked and eventually implemented. I think geohashes  
> are neat but an implementation detail that you wouldn't even have to be  
> aware of if the search platform has all the spatial features you need.
> 
> p.s. I'll have to look at your "geotools" (not to be confused with _the_  
> GeoTools at [geotools.org](http://geotools.org)) some time, for possible re-use of relevant  
> algorithms in Spatial4j (the spatial dependency of Lucene-spatial that I  
> work on).
> 
> Cheers,  
> David Smiley
> 
> On Wednesday, March 6, 2013 4:18:08 AM UTC-5, Jilles van Gurp wrote:
> 
> > No, not really. The way geohashes work is that they are pretty much  
> > rectangular themselves. So shortening the geohash prefix increases the size  
> > of the rectangle. The problem is that you can't move them around. So, you'd  
> > need multiple geohashes to cover an arbitrary bounding box unless the  
> > bounding box happens to overlap exactly with a single geohash..
> > 
> > What you can do is calculate the set of geohashes that cover a particular  
> > boundingbox (or any polygon) and use smaller prefixes to cover the insides  
> > and larger ones for the boundaries. That is pretty much what geo\_shape does  
> > but you can also do it manually and associate the geohashes with a field.  
> > Then you simply use prefix queries to search for anything that overlaps  
> > with the shape.
> > 
> > I've done this before and I have a library to support the geohash  
> > manipulation: [GitHub - jillesvangurp/geotools](https://github.com/jillesvangurp/geotools)
> > 
> > Jilles
> > 
> > On Wednesday, March 6, 2013 9:57:31 AM UTC+1, Gian Luca Ortelli wrote:
> > 
> > > Hi,
> > > 
> > > I read on the docs that you can define the bounding box using 2 geohash  
> > > values for the top left and bottom right corners. Is there a way to specify  
> > > the bounding box using a single geohash value? Typically, it would be a  
> > > value with less than 12 chars, to search all the documents containing it as  
> > > a prefix.
> > > 
> > > Thanks,  
> > > Gianluca

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**Author:** ![Gian\_Luca\_Ortelli](https://avatars.discourse-cdn.com/v4/letter/g/e68b1a/32.png) [@Gian\_Luca\_Ortelli](https://discuss.elastic.co/u/Gian_Luca_Ortelli)\
**Post date:** [March 7, 2013, 9:07am UTC](https://discuss.elastic.co/t/doing-bounding-box-filtering-using-a-geohash-prefix/11030/8 "2013-03-07T09:07:39Z")

</div>

Hi David,

About my use case:

I need to fetch documents from elasticsearch to display them on a map,  
grouping together icons that would otherwise overlap.

I decided to group using the geohash of the location of a document; for a  
certain level of zoom, I consider only the n-length prefix of the  
geohashes, and group together documents having the same prefix. In short,  
it's a grid based clustering algorithm, where the grid cells are defined by  
the geohash encoding.

The result is quite good. The missing piece is that the client must be able  
to ask all the documents belonging to a certain group. Since the client  
already knows the geohash prefix of the group (i.e., the common prefix of  
all the documents belonging to the group), the most straightforward  
solution would be to just use that value in the query.

A prefix query on the geohash is a solution; but if I should translate my  
need into a feature request, it would be a variation of the syntax for the  
bounding box filter, like below:

{  
"filtered" : {  
"query" : {  
"match\_all" : {}  
},  
"filter" : {  
"geo\_bounding\_box" : {  
"pin.location" : {

- 

```
               **"cell" : "drm3btev"*,
          }

      }
  }

```

}  
}

Gianluca

On Wednesday, March 6, 2013 9:09:41 PM UTC+1, David Smiley wrote:

> Hi Jilles,
> 
> I'm David Smiley, committer on Lucene/Solr specializing in spatial. I did  
> much of the spatial implementation that I believe Elasticsearch now uses.  
> Jilles, are there spatial features that Elasticsearch isn't offering that  
> require you to work with geohashes & what'not at the user level as you  
> describe? If so, perhaps these use-cases are en-route to Elasticsearch via  
> Lucene up-stream eventually, and if not then maybe you should add feature  
> requests so they get tracked and eventually implemented. I think geohashes  
> are neat but an implementation detail that you wouldn't even have to be  
> aware of if the search platform has all the spatial features you need.
> 
> p.s. I'll have to look at your "geotools" (not to be confused with _the_  
> GeoTools at [geotools.org](http://geotools.org)) some time, for possible re-use of relevant  
> algorithms in Spatial4j (the spatial dependency of Lucene-spatial that I  
> work on).
> 
> Cheers,  
> David Smiley
> 
> On Wednesday, March 6, 2013 4:18:08 AM UTC-5, Jilles van Gurp wrote:
> 
> > No, not really. The way geohashes work is that they are pretty much  
> > rectangular themselves. So shortening the geohash prefix increases the size  
> > of the rectangle. The problem is that you can't move them around. So, you'd  
> > need multiple geohashes to cover an arbitrary bounding box unless the  
> > bounding box happens to overlap exactly with a single geohash..
> > 
> > What you can do is calculate the set of geohashes that cover a particular  
> > boundingbox (or any polygon) and use smaller prefixes to cover the insides  
> > and larger ones for the boundaries. That is pretty much what geo\_shape does  
> > but you can also do it manually and associate the geohashes with a field.  
> > Then you simply use prefix queries to search for anything that overlaps  
> > with the shape.
> > 
> > I've done this before and I have a library to support the geohash  
> > manipulation: [GitHub - jillesvangurp/geotools](https://github.com/jillesvangurp/geotools)
> > 
> > Jilles
> > 
> > On Wednesday, March 6, 2013 9:57:31 AM UTC+1, Gian Luca Ortelli wrote:
> > 
> > > Hi,
> > > 
> > > I read on the docs that you can define the bounding box using 2 geohash  
> > > values for the top left and bottom right corners. Is there a way to specify  
> > > the bounding box using a single geohash value? Typically, it would be a  
> > > value with less than 12 chars, to search all the documents containing it as  
> > > a prefix.
> > > 
> > > Thanks,  
> > > Gianluca

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**Author:** ![David\_Smiley](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/david_smiley/32/2451_2.png) [@David\_Smiley](https://discuss.elastic.co/u/David_Smiley)\
**Post date:** [March 7, 2013, 8:02pm UTC](https://discuss.elastic.co/t/doing-bounding-box-filtering-using-a-geohash-prefix/11030/9 "2013-03-07T20:02:29Z")

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Sounds great. I recently started doing something similar and I'll try and  
see how this might be baked in. However I think this is something that  
would be at the ES or Solr levels, not at the Lucene level, because it gets  
into faceting. You mentioned "grouping" but my approach uses faceting.

~ David

On Thu, Mar 7, 2013 at 4:07 AM, Gian Luca Ortelli \<  
gianluca.ortelli@trifork.nl\> wrote:

> Hi David,
> 
> About my use case:
> 
> I need to fetch documents from elasticsearch to display them on a map,  
> grouping together icons that would otherwise overlap.
> 
> I decided to group using the geohash of the location of a document; for a  
> certain level of zoom, I consider only the n-length prefix of the  
> geohashes, and group together documents having the same prefix. In short,  
> it's a grid based clustering algorithm, where the grid cells are defined by  
> the geohash encoding.
> 
> The result is quite good. The missing piece is that the client must be  
> able to ask all the documents belonging to a certain group. Since the  
> client already knows the geohash prefix of the group (i.e., the common  
> prefix of all the documents belonging to the group), the most  
> straightforward solution would be to just use that value in the query.
> 
> A prefix query on the geohash is a solution; but if I should translate my  
> need into a feature request, it would be a variation of the syntax for the  
> bounding box filter, like below:
> 
> {  
> "filtered" : {  
> "query" : {  
> "match\_all" : {}  
> },  
> "filter" : {  
> "geo\_bounding\_box" : {  
> "pin.location" : {
> 
> - 
> 
> ```
> **"cell" : "drm3btev"*,
> }
> 
> }
> }
> 
> ```
> 
> }  
> }
> 
> Gianluca
> 
> On Wednesday, March 6, 2013 9:09:41 PM UTC+1, David Smiley wrote:
> 
> > Hi Jilles,
> > 
> > I'm David Smiley, committer on Lucene/Solr specializing in spatial. I  
> > did much of the spatial implementation that I believe Elasticsearch now  
> > uses. Jilles, are there spatial features that Elasticsearch isn't offering  
> > that require you to work with geohashes & what'not at the user level as you  
> > describe? If so, perhaps these use-cases are en-route to Elasticsearch via  
> > Lucene up-stream eventually, and if not then maybe you should add feature  
> > requests so they get tracked and eventually implemented. I think geohashes  
> > are neat but an implementation detail that you wouldn't even have to be  
> > aware of if the search platform has all the spatial features you need.
> > 
> > p.s. I'll have to look at your "geotools" (not to be confused with _the_  
> > GeoTools at [geotools.org](http://geotools.org)) some time, for possible re-use of relevant  
> > algorithms in Spatial4j (the spatial dependency of Lucene-spatial that I  
> > work on).
> > 
> > Cheers,  
> > David Smiley
> > 
> > On Wednesday, March 6, 2013 4:18:08 AM UTC-5, Jilles van Gurp wrote:
> > 
> > > No, not really. The way geohashes work is that they are pretty much  
> > > rectangular themselves. So shortening the geohash prefix increases the size  
> > > of the rectangle. The problem is that you can't move them around. So, you'd  
> > > need multiple geohashes to cover an arbitrary bounding box unless the  
> > > bounding box happens to overlap exactly with a single geohash..
> > > 
> > > What you can do is calculate the set of geohashes that cover a  
> > > particular boundingbox (or any polygon) and use smaller prefixes to cover  
> > > the insides and larger ones for the boundaries. That is pretty much what  
> > > geo\_shape does but you can also do it manually and associate the geohashes  
> > > with a field. Then you simply use prefix queries to search for anything  
> > > that overlaps with the shape.
> > > 
> > > I've done this before and I have a library to support the geohash  
> > > manipulation: [https://github](https://github).\*\*com/jillesvangurp/geotools[https://github.com/jillesvangurp/geotools](https://github.com/jillesvangurp/geotools)
> > > 
> > > Jilles
> > > 
> > > On Wednesday, March 6, 2013 9:57:31 AM UTC+1, Gian Luca Ortelli wrote:
> > > 
> > > > Hi,
> > > > 
> > > > I read on the docs that you can define the bounding box using 2 geohash  
> > > > values for the top left and bottom right corners. Is there a way to specify  
> > > > the bounding box using a single geohash value? Typically, it would be a  
> > > > value with less than 12 chars, to search all the documents containing it as  
> > > > a prefix.
> > > > 
> > > > Thanks,  
> > > > Gianluca
> > > 
> > > --  
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**Author:** ![Jilles\_van\_Gurp](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/jilles_van_gurp/32/879_2.png) [@Jilles\_van\_Gurp](https://discuss.elastic.co/u/Jilles_van_Gurp)\
**Post date:** [March 13, 2013, 9:51am UTC](https://discuss.elastic.co/t/doing-bounding-box-filtering-using-a-geohash-prefix/11030/10 "2013-03-13T09:51:27Z")

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FYI, I have renamed the geotools project. It is now named  
geogeometry: [GitHub - jillesvangurp/geogeometry: GeoGeometry is a set of algorithms and functions for manipulating geo hashes and geometric shapes with geo coordinates.](https://github.com/jillesvangurp/geogeometry)

> I'm aware that my choice of geotools as a name was a bit unfortunate given  
> the other project with the same name. I might have to rename it ;-). My  
> intention with it was to keep things simple and implement some generic  
> things that I need to implement geospatial search. In my view this is a  
> very simple problem: given a shape, cover it with geohashes, index them and  
> use wildcard queries to find things back. You don't even need Lucene for  
> this and I have used a similar approach with mysql and couchdb in the past.

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**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, 2:46am UTC](https://discuss.elastic.co/t/doing-bounding-box-filtering-using-a-geohash-prefix/11030/11 "2017-07-06T02:46:48Z")

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