Spatial search, nested docs, feature density

[Leila Deljkovic <le...@koordinates.com>]

Hi,

https://lucene.apache.org/solr/guide/7_0/uploading-data-with-index-handlers.html#UploadingDatawithIndexHandlers-NestedChildDocuments <https://lucene.apache.org/solr/guide/7_0/uploading-data-with-index-handlers.html#UploadingDatawithIndexHandlers-NestedChildDocuments>

I have never used nested documents, but a bit of background on what I’m doing is that a spatial data layer consisting of features (points, lines, polygons, or an aerial image) is split up into sections (grid cells) based on the density of these features over the layer; smaller grid cells indicate high density of features in that area. 

I need to rank results based on density of features and whether dense areas of the layer overlap with the region of space on a map I am searching in. This is important because a layer could cover an entire country, for example if I query for “roads”, the layer would be dense in urban areas as there are more roads there, and less dense in rural areas, and if I am searching for a particular city, this layer would be of interest to me even though it covers the entire country. The idea is for the original layer to be the parent document (which is what should be returned when a query is made), and the child documents are the individual grid cells (which will hold the geometry of the cell and a density field for the features inside the cell). 

I would like to know if it is possible to rank the parent document based on a function which aggregates fields from the child documents (in this case, the density field). There is not much info on this that I could find online.

Thanks

Re: Spatial search, nested docs, feature density

[Mikhail Khludnev <mk...@apache.org>]

The problem itself sounds really challenging, but literally two point from
the last question are:-
 -
https://lucene.apache.org/solr/guide/6_6/other-parsers.html#OtherParsers-Scoring
 - find field in
https://lucene.apache.org/solr/guide/6_6/function-queries.html#FunctionQueries-AvailableFunctions


On Thu, Jan 11, 2018 at 2:13 AM, Leila Deljkovic <
leila.deljkovic@koordinates.com> wrote:

> Hi,
>
> https://lucene.apache.org/solr/guide/7_0/uploading-data-
> with-index-handlers.html#UploadingDatawithIndexHandlers
> -NestedChildDocuments <https://lucene.apache.org/
> solr/guide/7_0/uploading-data-with-index-handlers.html#
> UploadingDatawithIndexHandlers-NestedChildDocuments>
>
> I have never used nested documents, but a bit of background on what I’m
> doing is that a spatial data layer consisting of features (points, lines,
> polygons, or an aerial image) is split up into sections (grid cells) based
> on the density of these features over the layer; smaller grid cells
> indicate high density of features in that area.
>
> I need to rank results based on density of features and whether dense
> areas of the layer overlap with the region of space on a map I am searching
> in. This is important because a layer could cover an entire country, for
> example if I query for “roads”, the layer would be dense in urban areas as
> there are more roads there, and less dense in rural areas, and if I am
> searching for a particular city, this layer would be of interest to me even
> though it covers the entire country. The idea is for the original layer to
> be the parent document (which is what should be returned when a query is
> made), and the child documents are the individual grid cells (which will
> hold the geometry of the cell and a density field for the features inside
> the cell).
>
> I would like to know if it is possible to rank the parent document based
> on a function which aggregates fields from the child documents (in this
> case, the density field). There is not much info on this that I could find
> online.
>
> Thanks




-- 
Sincerely yours
Mikhail Khludnev